To test a Web Service you must create a windows application or web application to consume this service? It is True/False?
FALSEHow many classes can a single.NET DLL contain?
Answer1:
As many

Answer2:
One or more

What are good ADO.NET object(s) to replace the ADO Recordset object?
The differences includes
In ADO, the in-memory representation of data is the recordset.
In ADO.net, it is the dataset
A recordset looks like a single table in ADO
In contrast, a dataset is a collection of one or more tables in ADO.net
ADO is designed primarily for connected access
ADO.net the disconnected access to the database is used
In ADO you communicate with the database by making calls to an OLE DB provider.
In ADO.NET you communicate with the database through a data adapter (an OleDbDataAdapter, SqlDataAdapter, OdbcDataAdapter, or OracleDataAdapter object), which makes calls to an OLE DB provider or the APIs provided by the underlying data source.
In ADO you cant update the database from the recordset. ADO.NET the data adapter allows you to control how the changes to the dataset are transmitted to the database.

On order to get assembly info which namespace we should import?
System.Reflection Namespace

How do you declare a static variable and what is its lifetime? Give an example.
Answer1
static int Myint–The life time is during the entire application.
br> Answer2
The static modifier is used to declare a static member, which belongs to the type itself rather than to a specific object. The static modifier can be used with fields, methods, properties, operators, events and constructors, but cannot be used with indexers, destructors, or types. In C#, the static keyword indicates a class variable. In VB, the equivalent keyword is Shared. Its scoped to the class in which it occurs.

Example
a. Static int var //in c#.net
b. static void Time( ) //in c#.net

How do you get records number from 5 to 15 in a dataset of 100 records? Write code.
Answer1
DataSet ds1=new DataSet(); String strCon=”data source=IBM-6BC8A0DACEF;initial catalog=pubs;integrated security=SSPI;persist” +” security info=False;user
id=sa;workstation id=IBM-6BC8A0DACEF;packet size=4096?;
String strCom1=”SELECT * FROM employee”;
SqlDataAdapter sqlDa1=new SqlDataAdapter(strCom1,strCon);
ds1.Tables.Add(”employee”);
sqlDa1.Fill(ds1,40,50,ds1.Tables[”employee”].TableName);
DataGrid dg1.DataSource=ds1.Tables[”employee”].DefaultView;
dg1.DataBind();

Answer2
OleDbConnection1.Open()
OleDbDataAdapter1.Fill(DataSet21, 5, 15, “tab”)
This will fill the dataset with the records starting at 5 to 15
.NET Database interview questions

How do you call and execute a Stored Procedure in.NET? Give an example.
Answer1
ds1=new DataSet();
sqlCon1=new SqlConnection(connectionstring);
String strCom1=”byroyalty”;
sqlCom1=new SqlCommand(strCom1,sqlCon1);
sqlCom1.CommandType=CommandType.StoredProcedure;
sqlDa1=new SqlDataAdapter(sqlCom1);
SqlParameter myPar=new SqlParameter(”@percentage”,SqlDbType.Int);
sqlCom1.Parameters.Add (myPar);
myPar.Value=40;
sqlDa1.Fill(ds1);
dg1.DataSource=ds1;
dg1.DataBind();

Answer2
Yes
Dim cn as new OleDbConnection ( “Provider=Microsoft.Jet.OLEDB.4.0;”+ _
“Data Source=C:\Documents and Settings\User\My Documents\Visual Studio Projects\1209\db1.mdb”+ _
“User ID=Admin;”+ _
“Password=;”);
Dim cmd As New OleDbCommand(”Products”, cn)
cmd.CommandType = CommandType.StoredProcedure
Dim da As New OleDataAdapter(cmd)
Dim ds As New DataSet()
da.Fill(ds, “Products”)
DataGrid1.DataSource = ds.Tables(”Products”)

What is the maximum length of a varchar in SQL Server?
Answer1
VARCHAR[(n)]
Null-terminated Unicode character string of length n,
with a maximum of 255 characters. If n is not supplied, then 1 is assumed.

Answer2
8000

Answer3
The business logic is the aspx.cs or the aspx.vb where the code is being written. The presentation logic is done with .aspx extention.

How do you define an integer in SQL Server?
We define integer in Sql server as
var_name int

How do you separate business logic while creating an ASP.NET application?
There are two level of asp.net debugging
1. Page level debugging
For this we have to edit the page level debugging enable the trace to true in the line in the html format of the page.
%@ Page Language=”vb” trace=”true”AutoEventWireup=”false” Codebehind=”WebForm1.aspx.vb” Inherits=”WebApplication2.WebForm1?>

2. You can enable the debugging in the application level for this
Edit the following trace value in web.config file
Enable trace enabled=true.

If there is a calendar control to be included in each page of your application, and and we do not intend to use the Microsoft-provided calendar control, how do you develop it? Do you copy and paste the code into each and every page of your application?

Create the Calendar User Control
The control we will create will contain a calendar control and a label which has the corresponding date and time written
Steps are:-

Creating a CalenderControl
1) To begin, open Visual Studio .NET and begin a new C# Windows Control Library.
2) You may name it whatever you like, for this sample the project name will be CalenderControl

Using the Calender Control in a Windows Application
It’s just like adding any other control like a button or a label.
1) First, create a new Windows Application project named: CustomControl.
2) Add a reference to the Calender Control DLL named: CalenderControl.dll.
3) Now you a can customize the Toolbox:
Right-Click the Toolbox> .NET Framework Components> Browse> select the CalenderControl.dll.
4)The Calender Control is now added to the Toolbox and can be inserted in Windows Form as any other control. The control itself will take care of the date display

How can you deploy an asp.net application ?
You can deploy an ASP.NET Web application using any one of the following three deployment options.
a) Deployment using VS.NET installer
b) Using the Copy Project option in VS .NET
c) XCOPY Deployment

Explain similarities and differences between Java and.NET?
Comparing Java and .NET is comparing apples and oranges. Either the question needs to be to compare Java and C# or J2EE and .NET.

What are the XML files that are important in developing an ASP.NET application?
The XML file necessary for the for developing an asp.net application is Web.config

Specify the best ways to store variables so that we can access them in various pages of ASP.NET application?
Declare the variables in Global.aspx

How many objects are there in ASP?
Answer1
8 objects, they are request,response, server,application,session,file, dictionary, textstream.

Answer2
There are 6 objects in ASP.net
a) Server
b) Session
c) Application
d) ObjectContext
e) Response
f) Request

Which DLL file is needed to be registered for ASP?
The dll needed for the ASP.net is SYSTEM.WEB.dll

Is there any inbuilt paging (for example shoping cart, which will show next 10 records without refreshing) in ASP? How will you do pating?
Use DataGrid control which has in-built paging features for the purpose.

What does Server.MapPath do?
Answer1
srver.mappath() maps the path given in the argument to the server’s physical path.

Answer2
It returns the complete(absolute) path of the file used in parameter.

Answer3
It returns a string containing the physical path in the server’s file system that corresponds to the virtual or relative path specified by the Path argument.

Name atleast three methods of response object other than Redirect.
Answer1
a) Response.Clear( )
Clears the content of the current output stream.
b) Response.Close( )
Closes the network socket for the current response.
c) Response.End( )
Stops processing the current request and sends all buffered content to the client immediately.

Answer2
methods of Response is Redirect a. Transfer

Name atleast two methods of response object other than Transfer.
a) Response.ClearContent( )
Clears the content of the current output stream.
b) Response.ClearHeaders( )
Clears the HTTP headers from the current output stream.

What is State?
It is the property of the web forms.
ASP.NET provides four types of state:
Application state
Session state
Cookie state
View state.

Explain differences between ADO and DAO.
dao- can access only access database
ado- can access any databases

How many types of cookies are there?
2 types, persistant and impersistant.

How many types of cookies are there?
Answer1
Two type of cookeies.
a) single valued eg request.cookies(”UserName”).value=”Mahesh”
b)Multivalued cookies. These are used in the way collections are used.
e.g.
request.cookies(”CookiName”)(”UserName”)=”Mahesh”
request.cookies(”CookiName”)(”UserID”)=”ABC003?
rember no value method in multivalued cooki

Answer2
There are two types of cookies:
Session cookies
Persistent cookies

Tell few steps for optimizing (for speed and resource) ASP page/application.
Avoid mixing html code with asp code

Which command using Query Analyzer will give you the version of SQL Server and Operating System?
@@VERSION
Returns version, processor architecture, build date, and operating system for the current installation of SQL Server.

How to find the SQL server version from Query Analyser
Answer1
To determine which version of Microsoft SQL Server 2005 is running, connect to SQL Server 2005 by using SQL Server Management Studio, and then run the following Transact-SQL statement:
SELECT SERVERPROPERTY(’productversion’), SERVERPROPERTY (’productlevel’), SERVERPROPERTY (’edition’)
The results are:
• The product version (for example, “9.00.1399.06?)
. • The product level (for example, “RTM”).
• The edition (for example, “Enterprise Edition”).
For example, the result looks similar to:
9.00.1399.06 RTM Enterprise Edition

How to determine which version of SQL Server 2000 is running
To determine which version of SQL Server 2000 is running, connect to SQL Server 2000 by using Query Analyzer, and then run the following code:
SELECT SERVERPROPERTY(’productversion’), SERVERPROPERTY (’productlevel’), SERVERPROPERTY (’edition’)
The results are:
• The product version (for example, 8.00.534).
• The product level (for example, “RTM” or “SP2?).
• The edition (for example, “Standard Edition”). For example, the result looks similar to
:
8.00.534 RTM Standard Edition

Answer2
One can also use SELECT @@Version where the result would look like
Microsoft SQL Server 2005 - 9.00.1399.06 (Intel X86)
Oct 14 2005 00:33:37
Copyright (c) 1988-2005 Microsoft Corporation
Express Edition on Windows NT 5.1 (Build 2600: Service Pack 2)

Using query analyzer, name 3 ways you can get an accurate count of the number of records in a table.
Answer1.
a. Select count(*) from table1
b. SELECT object_name(id) ,rowcnt FROM sysindexes WHERE indid IN (1,0) AND OBJECTPROPERTY(id, ‘IsUserTable’) = 1
c. exec sp_table_validation @table = ‘authors’

Answer2.
SELECT count( * ) as totalrecords FROM employee
This will display total records under the name totalrecords in the table employee
use COUNT_BIG
Returns the number of items in a group.
@@ROWCOUNT
Returns the number of rows affected by the last statement.
Use this statement after an SQL select * statement, to retrieve the total number of rows in the table

To test a Web Service you must create a windows application or web application to consume this service? It is True/False?
FALSEHow many classes can a single.NET DLL contain?
Answer1:
As many

Answer2:
One or more

What are good ADO.NET object(s) to replace the ADO Recordset object?
The differences includes
In ADO, the in-memory representation of data is the recordset.
In ADO.net, it is the dataset
A recordset looks like a single table in ADO
In contrast, a dataset is a collection of one or more tables in ADO.net
ADO is designed primarily for connected access
ADO.net the disconnected access to the database is used
In ADO you communicate with the database by making calls to an OLE DB provider.
In ADO.NET you communicate with the database through a data adapter (an OleDbDataAdapter, SqlDataAdapter, OdbcDataAdapter, or OracleDataAdapter object), which makes calls to an OLE DB provider or the APIs provided by the underlying data source.
In ADO you cant update the database from the recordset. ADO.NET the data adapter allows you to control how the changes to the dataset are transmitted to the database.

On order to get assembly info which namespace we should import?
System.Reflection Namespace

How do you declare a static variable and what is its lifetime? Give an example.
Answer1
static int Myint–The life time is during the entire application.
br> Answer2
The static modifier is used to declare a static member, which belongs to the type itself rather than to a specific object. The static modifier can be used with fields, methods, properties, operators, events and constructors, but cannot be used with indexers, destructors, or types. In C#, the static keyword indicates a class variable. In VB, the equivalent keyword is Shared. Its scoped to the class in which it occurs.

Example
a. Static int var //in c#.net
b. static void Time( ) //in c#.net

How do you get records number from 5 to 15 in a dataset of 100 records? Write code.
Answer1
DataSet ds1=new DataSet(); String strCon=”data source=IBM-6BC8A0DACEF;initial catalog=pubs;integrated security=SSPI;persist” +” security info=False;user
id=sa;workstation id=IBM-6BC8A0DACEF;packet size=4096?;
String strCom1=”SELECT * FROM employee”;
SqlDataAdapter sqlDa1=new SqlDataAdapter(strCom1,strCon);
ds1.Tables.Add(”employee”);
sqlDa1.Fill(ds1,40,50,ds1.Tables[”employee”].TableName);
DataGrid dg1.DataSource=ds1.Tables[”employee”].DefaultView;
dg1.DataBind();

Answer2
OleDbConnection1.Open()
OleDbDataAdapter1.Fill(DataSet21, 5, 15, “tab”)
This will fill the dataset with the records starting at 5 to 15
.NET Database interview questions

How do you call and execute a Stored Procedure in.NET? Give an example.
Answer1
ds1=new DataSet();
sqlCon1=new SqlConnection(connectionstring);
String strCom1=”byroyalty”;
sqlCom1=new SqlCommand(strCom1,sqlCon1);
sqlCom1.CommandType=CommandType.StoredProcedure;
sqlDa1=new SqlDataAdapter(sqlCom1);
SqlParameter myPar=new SqlParameter(”@percentage”,SqlDbType.Int);
sqlCom1.Parameters.Add (myPar);
myPar.Value=40;
sqlDa1.Fill(ds1);
dg1.DataSource=ds1;
dg1.DataBind();

Answer2
Yes
Dim cn as new OleDbConnection ( “Provider=Microsoft.Jet.OLEDB.4.0;”+ _
“Data Source=C:\Documents and Settings\User\My Documents\Visual Studio Projects\1209\db1.mdb”+ _
“User ID=Admin;”+ _
“Password=;”);
Dim cmd As New OleDbCommand(”Products”, cn)
cmd.CommandType = CommandType.StoredProcedure
Dim da As New OleDataAdapter(cmd)
Dim ds As New DataSet()
da.Fill(ds, “Products”)
DataGrid1.DataSource = ds.Tables(”Products”)

What is the maximum length of a varchar in SQL Server?
Answer1
VARCHAR[(n)]
Null-terminated Unicode character string of length n,
with a maximum of 255 characters. If n is not supplied, then 1 is assumed.

Answer2
8000

Answer3
The business logic is the aspx.cs or the aspx.vb where the code is being written. The presentation logic is done with .aspx extention.

How do you define an integer in SQL Server?
We define integer in Sql server as
var_name int

How do you separate business logic while creating an ASP.NET application?
There are two level of asp.net debugging
1. Page level debugging
For this we have to edit the page level debugging enable the trace to true in the line in the html format of the page.
%@ Page Language=”vb” trace=”true”AutoEventWireup=”false” Codebehind=”WebForm1.aspx.vb” Inherits=”WebApplication2.WebForm1?>

2. You can enable the debugging in the application level for this
Edit the following trace value in web.config file
Enable trace enabled=true.

If there is a calendar control to be included in each page of your application, and and we do not intend to use the Microsoft-provided calendar control, how do you develop it? Do you copy and paste the code into each and every page of your application?

Create the Calendar User Control
The control we will create will contain a calendar control and a label which has the corresponding date and time written
Steps are:-

Creating a CalenderControl
1) To begin, open Visual Studio .NET and begin a new C# Windows Control Library.
2) You may name it whatever you like, for this sample the project name will be CalenderControl

Using the Calender Control in a Windows Application
It’s just like adding any other control like a button or a label.
1) First, create a new Windows Application project named: CustomControl.
2) Add a reference to the Calender Control DLL named: CalenderControl.dll.
3) Now you a can customize the Toolbox:
Right-Click the Toolbox> .NET Framework Components> Browse> select the CalenderControl.dll.
4)The Calender Control is now added to the Toolbox and can be inserted in Windows Form as any other control. The control itself will take care of the date display

How can you deploy an asp.net application ?
You can deploy an ASP.NET Web application using any one of the following three deployment options.
a) Deployment using VS.NET installer
b) Using the Copy Project option in VS .NET
c) XCOPY Deployment

Explain similarities and differences between Java and.NET?
Comparing Java and .NET is comparing apples and oranges. Either the question needs to be to compare Java and C# or J2EE and .NET.

What are the XML files that are important in developing an ASP.NET application?
The XML file necessary for the for developing an asp.net application is Web.config

Specify the best ways to store variables so that we can access them in various pages of ASP.NET application?
Declare the variables in Global.aspx

How many objects are there in ASP?
Answer1
8 objects, they are request,response, server,application,session,file, dictionary, textstream.

Answer2
There are 6 objects in ASP.net
a) Server
b) Session
c) Application
d) ObjectContext
e) Response
f) Request

Which DLL file is needed to be registered for ASP?
The dll needed for the ASP.net is SYSTEM.WEB.dll

Is there any inbuilt paging (for example shoping cart, which will show next 10 records without refreshing) in ASP? How will you do pating?
Use DataGrid control which has in-built paging features for the purpose.

What does Server.MapPath do?
Answer1
srver.mappath() maps the path given in the argument to the server’s physical path.

Answer2
It returns the complete(absolute) path of the file used in parameter.

Answer3
It returns a string containing the physical path in the server’s file system that corresponds to the virtual or relative path specified by the Path argument.

Name atleast three methods of response object other than Redirect.
Answer1
a) Response.Clear( )
Clears the content of the current output stream.
b) Response.Close( )
Closes the network socket for the current response.
c) Response.End( )
Stops processing the current request and sends all buffered content to the client immediately.

Answer2
methods of Response is Redirect a. Transfer

Name atleast two methods of response object other than Transfer.
a) Response.ClearContent( )
Clears the content of the current output stream.
b) Response.ClearHeaders( )
Clears the HTTP headers from the current output stream.

What is State?
It is the property of the web forms.
ASP.NET provides four types of state:
Application state
Session state
Cookie state
View state.

Explain differences between ADO and DAO.
dao- can access only access database
ado- can access any databases

How many types of cookies are there?
2 types, persistant and impersistant.

How many types of cookies are there?
Answer1
Two type of cookeies.
a) single valued eg request.cookies(”UserName”).value=”Mahesh”
b)Multivalued cookies. These are used in the way collections are used.
e.g.
request.cookies(”CookiName”)(”UserName”)=”Mahesh”
request.cookies(”CookiName”)(”UserID”)=”ABC003?
rember no value method in multivalued cooki

Answer2
There are two types of cookies:
Session cookies
Persistent cookies

Tell few steps for optimizing (for speed and resource) ASP page/application.
Avoid mixing html code with asp code

Which command using Query Analyzer will give you the version of SQL Server and Operating System?
@@VERSION
Returns version, processor architecture, build date, and operating system for the current installation of SQL Server.

How to find the SQL server version from Query Analyser
Answer1
To determine which version of Microsoft SQL Server 2005 is running, connect to SQL Server 2005 by using SQL Server Management Studio, and then run the following Transact-SQL statement:
SELECT SERVERPROPERTY(’productversion’), SERVERPROPERTY (’productlevel’), SERVERPROPERTY (’edition’)
The results are:
• The product version (for example, “9.00.1399.06?)
. • The product level (for example, “RTM”).
• The edition (for example, “Enterprise Edition”).
For example, the result looks similar to:
9.00.1399.06 RTM Enterprise Edition

How to determine which version of SQL Server 2000 is running
To determine which version of SQL Server 2000 is running, connect to SQL Server 2000 by using Query Analyzer, and then run the following code:
SELECT SERVERPROPERTY(’productversion’), SERVERPROPERTY (’productlevel’), SERVERPROPERTY (’edition’)
The results are:
• The product version (for example, 8.00.534).
• The product level (for example, “RTM” or “SP2?).
• The edition (for example, “Standard Edition”). For example, the result looks similar to
:
8.00.534 RTM Standard Edition

Answer2
One can also use SELECT @@Version where the result would look like
Microsoft SQL Server 2005 - 9.00.1399.06 (Intel X86)
Oct 14 2005 00:33:37
Copyright (c) 1988-2005 Microsoft Corporation
Express Edition on Windows NT 5.1 (Build 2600: Service Pack 2)

Using query analyzer, name 3 ways you can get an accurate count of the number of records in a table.
Answer1.
a. Select count(*) from table1
b. SELECT object_name(id) ,rowcnt FROM sysindexes WHERE indid IN (1,0) AND OBJECTPROPERTY(id, ‘IsUserTable’) = 1
c. exec sp_table_validation @table = ‘authors’

Answer2.
SELECT count( * ) as totalrecords FROM employee
This will display total records under the name totalrecords in the table employee
use COUNT_BIG
Returns the number of items in a group.
@@ROWCOUNT
Returns the number of rows affected by the last statement.
Use this statement after an SQL select * statement, to retrieve the total number of rows in the table

Program Input, Edit, Hapus (Manipulasi data) merupakan program standar yang selalu ada pada saat seorang programmer membuat aplikasi.

Kebisaan membuat program dari zaman Basic, Pascal, clipper, foxpro sampai ke Visual Basic 5 dan Visual Basic 6 yang selalu mengandalkan kode program dalam membangun program, bagi saya masih terbawa bawa ke era Visual yang telah didukung dengan Wizard.

Pada artikel kali ini saya coba memaparkan cara membuat program Input, Edit, Hapus dengan mengambil contoh pengolahan data supplier, hampir 100% saya pakai code program.

Contoh yang dibahas sifatnya sangat dasar sekali, jadi untuk rekan rekan yang sudah sangat berpengalaman dalam pemrograman dimohon saran dan info yang membangun demi kebaikan kemampuan programming dimasa datang.

Untuk rekan pemula mudahan mudahan artikel ini bisa membantu dalam memperdalam pengetahuan programming

Mari kita mulai saja.

Siapkan sebuah database di SQL Server 2005, pada komputer saya servernya saya beri nama ISLAM, dengan nama database GUDANG

Untuk server pembaca silahkan sesuaikan sendiri sesuai keinginan.

Kita lanjutkan

Buat table supplier dengan susunan field seperti gambar berikut :

Sekarang aktifkan Visual Basic.NET 2005 dan buat sebuah project baru namanya juga terserah anda. (saya sendiri memberi nama project ini GUDANG)

Siapkan sebuah Module baru yang berfungsi untuk membuat koneksi kedatabase atau tempat menyimpan fungsi atau prosedur yang kita butuhkan dalam pembuatan program.

Langkah pembuatan module : klik kanan nama project yang ada di Window Solution Explorer, lalu pilih Add --> Module. Secara default VB akan memberi nama Module1.

berikut ini gambar Solution Explorer :

Pada jendela Code program Module1 masukkan kode berikut :

Imports System.Data.SqlClient

Module Module1

Public Function Koneksi() As SqlConnection

Dim Conn As New SqlConnection

Conn = New SqlConnection("server=islam; database=gudang; user=sa;password=intan;")

Conn.Open()

Return Conn

End Function

End Module

Sekali lagi untuk nama server, database, user dan password sesuaikan dengan komputer yang anda pakai.

Tahap selanjutnya siapkan form baru dengan contoh disain seperti gambar berikut.

Komponen yang ada pada form terdiri dari 6 Label (text label sesuaikan dengan gambar),

6 Buah Textbox Masing masing diberi nama :

TextKode

TextNama

TextAlamat

TextTelepon

TextKontakPerson

TextEmail

6 Buah Button, masing diberi nama :

ButtonTambah

ButtonSimpan

ButtonHapus

ButtonUpdate

ButtunKeluar

Buttun1 (Loading data)

1 Buah DatagridView dengan nama GridSupplier.

Saatnya Coding…...,

Setelah semua komponen tersusun dalam Form saat kita melakukan coding program.

Pada Menu Bar, pilih menu View à Code

Pada bagian atas ketikan kode berikut untuk meng-import Class Data SQL sehingga kita bisa melakukan koneksi ke database.

Imports System.Data.SqlClient

Selanjutnya pelajari code program berikut baris perbaris sambil memperhatikan komentar kode program yang saya sisipkan pada setiap prosedur.

Kode komentar selalu diawali dengan tanda kutip satu (‘)

Public Class Supplier

‘ Siapkan variabel keneksi

Dim koneksi = Module1.Koneksi

‘Prosedur load form (aktifkan denfan double klik pada form)

Private Sub Supplier_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

‘ panggil prosedur PanggilData

PanggilData()

ButtonSimpan.Enabled = False

ButtonHapus.Enabled = False

ButtonUpdate.Enabled = False

End Sub

‘Prosedur membuat datagridview memiliki warna Alternate

Sub GridBerwarna()

With Me.GridSupplier

.RowsDefaultCellStyle.BackColor = Color.BlanchedAlmond

.AlternatingRowsDefaultCellStyle.BackColor = Color.Azure

End With

End Sub

‘ Prosedur panggildata

Sub PanggilData()

Dim Adapter As New SqlDataAdapter("select * from supplier", Module1.Koneksi)

Dim dt As New DataTable("Supplier")

Adapter.Fill(dt)

GridSupplier.DataSource = dt

Call GridBerwarna()

End Sub

‘Prosedur Form kosong (berfungsi untuk mengosongkan TetxBox dangan pengaturan focus)

Sub FormKosong()

TextKode.Text = ""

TextNama.Text = ""

TextAlamat.Text = ""

TextTelepon.Text = ""

TextKontakPerson.Text = ""

TextEmail.Text = ""

TextKode.Focus()

End Sub

‘Prosedur mengaktifkan TextBox

Sub FormHidup()

TextKode.Enabled = True

TextNama.Enabled = True

TextAlamat.Enabled = True

TextTelepon.Enabled = True

TextKontakPerson.Enabled = True

TextEmail.Enabled = True

End Sub

‘Prosedure Mengatur Button dan Textbox

Sub FormNormal()

Call FormKosong()

ButtonTambah.Enabled = True

ButtonHapus.Enabled = False

ButtonSimpan.Enabled = False

ButtonKeluar.Text = "&Keluar"

End Sub

‘Prosedur untuk tambah data

Private Sub ButtonTambah_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonTambah.Click

Call FormHidup()

Call FormKosong()

Call PanggilData()

ButtonSimpan.Enabled = True

ButtonTambah.Enabled = False

ButtonHapus.Enabled = False

ButtonUpdate.Enabled = False

ButtonKeluar.Text = "&Normal"

TextKode.Focus()

End Sub

‘Prosedur untuk simpan data

Private Sub ButtonSimpan_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonSimpan.Click

Dim Sql As String = String.Empty

'Cek Kode

‘Uji data apakah textKode tidak kosong

If TextKode.Text <> "" Then

'Jika tidak kosong tambahkan data

Sql = "INSERT INTO Supplier(KodeSupplier,NamaSupplier,AlamatSupplier,Telepon,KontakPerson,email)" _

& " VALUES ('" & TextKode.Text & "','" & TextNama.Text & "', '" & TextAlamat.Text & "', '" _

& TextTelepon.Text & "', '" & TextKontakPerson.Text & "', '" & TextEmail.Text & "')"

‘ Periksa hati-hati tanda kutip untuk setiap variabel, salah ketik mengakibatkan query anda tidak akan terbaca.

‘ Persiapan execusi Query Insert

Dim command As New SqlCommand(Sql, Module1.Koneksi)

command.ExecuteNonQuery()

Module1.Koneksi.Close()

‘ sampaikan pesan bahwa data telah tersimpan.

MessageBox.Show("Data dengan kode " & TextKode.Text & " Sudah disimpan", "Simpan data Sukses", MessageBoxButtons.OK, MessageBoxIcon.Information)

‘ sampaikan juga pesan jika penyimpanan gagal.

Else

MessageBox.Show("Isikan dulu data", "Simpan Gagal", MessageBoxButtons.OK, MessageBoxIcon.Information)

TextKode.Focus()

End If

‘ Panggil prosedur FormKosong dan prosedur panggil data.

Call FormKosong()

Call PanggilData()

End Sub

‘ ini prosedur untuk mengganti tab jadi enter dan prosedur untuk mencari apakah data pada text kode sudah pernah ada atau belum untuk menghindari redudansi data.

Private Sub TextKode_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextKode.KeyPress

If e.KeyChar = Chr(Keys.Enter) Then

'mengirim key tab

SendKeys.Send("{tab}")

End If

'buat koneksi untuk pencarian data yang sudah ada

Dim Adapter As New SqlDataAdapter("SELECT * from Supplier where KodeSupplier = '" _

& TextKode.Text & "'", Module1.Koneksi)

Dim dt As New DataTable("Supplier")

Adapter.Fill(dt)

'Jika data yang dicari ada

If dt.Rows.Count <> 0 Then

MessageBox.Show("Data dengan kode " & TextKode.Text & " Sudah ada, inputkan data lain", "Ditemukan data yang sama", MessageBoxButtons.OK, MessageBoxIcon.Information)

TextKode.Text = " "

End If

GridSupplier.DataSource = dt

End Sub

‘ ini prosedur untuk mengganti tab jadi enter

Private Sub TextNama_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextNama.KeyPress

'tab to enter

If e.KeyChar = Chr(Keys.Enter) Then

'mengirim key tab

SendKeys.Send("{tab}")

End If

End Sub

‘ ini prosedur untuk mengganti tab jadi enter

Private Sub TextAlamat_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextAlamat.KeyPress

'tab to enter

If e.KeyChar = Chr(Keys.Enter) Then

'mengirim key tab

SendKeys.Send("{tab}")

End If

End Sub

‘ ini prosedur untuk mengganti tab jadi enter

Private Sub TextTelepon_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextTelepon.KeyPress

'tab to enter

If e.KeyChar = Chr(Keys.Enter) Then

'mengirim key tab

SendKeys.Send("{tab}")

End If

End Sub

‘ ini prosedur untuk mengganti tab jadi enter

Private Sub TextKontakPerson_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextKontakPerson.KeyPress

'tab to enter

If e.KeyChar = Chr(Keys.Enter) Then

'mengirim key tab

SendKeys.Send("{tab}")

End If

End Sub

‘ ini prosedur untuk mengganti tab jadi enter

Private Sub TextEmail_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextEmail.KeyPress

'tab to enter

If e.KeyChar = Chr(Keys.Enter) Then

'mengirim key tab

SendKeys.Send("{tab}")

End If

End Sub

‘prosedur untuk menghapus data

Private Sub ButtonHapus_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonHapus.Click

If GridSupplier.CurrentRow.Index > -1 Then

Dim Sql As String = String.Empty

Sql = "Delete from Supplier where KodeSupplier = '" & TextKode.Text & "'"

Dim command As New SqlCommand(Sql, Module1.Koneksi)

command.ExecuteNonQuery()

Module1.Koneksi.Close()

MessageBox.Show("Data dengan kode " & TextKode.Text & " Sudah dihapus", "Penghapusan Sukses", MessageBoxButtons.OK, MessageBoxIcon.Information)

Call FormKosong()

Call PanggilData()

ButtonHapus.Enabled = False

ButtonUpdate.Enabled = False

Else

MessageBox.Show("Pilih dulu data yang akan dihapus", "Tidak ada data yang akan dihapus", MessageBoxButtons.OK, MessageBoxIcon.Information)

End If

End Sub

‘prosedur untuk Update data

Private Sub ButtonUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonUpdate.Click

Dim Sql As String = String.Empty

'Cek Kode

'Update

Sql = "UPDATE Supplier SET KodeSupplier= '" & TextKode.Text & "'," _

& "NamaSupplier='" & TextNama.Text & "',AlamatSupplier = '" & TextAlamat.Text & "'," _

& "Telepon='" & TextTelepon.Text & "',KontakPerson = '" & TextKontakPerson.Text & "'," _

& "email = '" & TextEmail.Text & "' WHERE kodeSupplier = '" & TextKode.Text & "'"

Dim command As New SqlCommand(Sql, Module1.Koneksi)

command.ExecuteNonQuery()

Module1.Koneksi.Close()

MessageBox.Show("Data dengan kode " & TextKode.Text & " Sudah diupdate", "Update data Sukses", MessageBoxButtons.OK, MessageBoxIcon.Information)

Call FormKosong()

Call PanggilData()

ButtonHapus.Enabled = False

ButtonUpdate.Enabled = False

End Sub

Private Sub ButtonKeluar_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonKeluar.Click

If ButtonKeluar.Text = "&Keluar" Then

Me.Close()

Else

Call FormNormal()

End If

End Sub

‘prosedur untuk loading data ke dataqridview (refresh data, setelah dilakukan query

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Call PanggilData()

End Sub

‘ini prosedur yang sangat berperan,karena prosedure ini akan membuat setiap baris yang cel yang kita klik pada data grid view, maka isi dari setiap field akan dikirim kedalam textbox, sehingga kita dapat melakukan manipulasi data.

Prosedure ini mirip dengan Binding manager, Insyallah akan kita bahas pada artikel berikutnya.

Private Sub GridSupplier_CellClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles GridSupplier.CellClick

Dim i As Integer

i = GridSupplier.CurrentRow.Index

TextKode.Text = GridSupplier.Item(0, i).Value

TextNama.Text = GridSupplier.Item(1, i).Value

TextAlamat.Text = GridSupplier.Item(2, i).Value

TextTelepon.Text = GridSupplier.Item(3, i).Value

TextKontakPerson.Text = GridSupplier.Item(4, i).Value

TextEmail.Text = GridSupplier.Item(5, i).Value

ButtonHapus.Enabled = True

ButtonUpdate.Enabled = True

End Sub

End Class

Sampai disini dulu artikel tentang Program input dan edit data dengan VB.NET 2005 dan SQL Server 2005, semoga menjadi ilmu yang bermanfaat. Saya sangat mengharapkan saran komentar anda, sehingga membuat ilmu pengetahuan berkembang, Salam programming

@pri

Penghujung Juli 2008, Sarijadi, Bandung

1. DataReaders have less overhead than DataSets and are more efficient.
2. DataReaders can be databound (i.e. to a DataGrid).
3. Iterated once through

but

1. DataSets are disconnected. They are like disconnected models of the database.
2. DataSets can be made into Session objects or files, for persistence
3. DataSets can provide access to more than one table and table relationships
4. DataSets can be bound to multiple controls
5. Reiterated through multiple times.
5. You can jump to a particular record or go backwards through a DataSet.
6. Ability to name your table

¹ My Library Syndication

In this post we will finalize the implementation of our 3-tier asp.net architecture, by developing a Web-based presentation layer.

So far, we have developed the data access and business layers. The implementation of UI, consists of methods and approaches for handling business and crud operations thorough a Web UI. In fact, there are several ways to present business objects and reflect the changes back to data base. Like:

1. Binding controls (i.e. GridView) directly to DataTables coming from business classes (i.e. by FetchAll method)
2. Binding controls (.e. GridView) to business classes using an IDataSource, like ObjectDataSouce control.
3. Mixing up the above methods.

If you opt the first option, you need to handle sorting and paging manually. It means that you have to write code for PageIndexChanged and Sorted methods. This might take several minutes for you to handle every details and make your development process too long and not productive.

A better approach is using ObjectDataSource. For using it, we have to prepare our business classes first. ObjectDataSoruce works with classes that DataObject attribute has been applied to them. Thus, open your business class (i.e. PersonBiz.cs), and apply DataObject attribute on it:

[DataObject]

public class PersonBiz
{ ...

Then we might specify four methods for doing Select/Insert/Update/Delete operations. However, I personally prefer to use Select method only and do the other operations manually. My reason is that, if I declare a method for Insert/Update methods, I will have to use GridView's (or similar controls) editing features and have to pass a lot of params to the Insert/Update methods. and I do not like it! :-)

Anyway, to mark a method as a Select method, we have to apply DataObjectMethod attribute on it. This attribute takes a parameter indicating which kind of method is it. For example, a select method can be declared like this:
[DataObjectMethod(DataObjectMethodType.Select)]
public DataTable FetchAll(...

If you are intended to use ObjectDataSource, your Select method must have a return value of type IENumerable, and preferably, it would better return a DataTable or DataView.Thus, FetchAll method returns a DataTable. It also has two parameters as follows:

[DataObjectMethod(DataObjectMethodType.Select)]
public DataTable FetchAll(int startRowIndex, int maximumRows)
{
PersonEntity entity = new PersonEntity();
innerDAL.Fill(entity, startRowIndex, maximumRows);
return entity;
}

As you see, the startRowIndex and maximumRows are used for paging. If you do not wish to manage paging, you may omit these two arguments.

To bind your UI control (i.e. GridView) to this method, put an ObjectDataSource on your web form. Then, choose Configure DataSource from it's smart tag. The Configure Data Source window will open:

Check the "Show only data components" and open the drop down list beside it. If nothing is seen, you have to build the BusinessLayer.Dll and put it in your website's Bin folder.

Select your business class and click Next. At the next step, you have to specify which methods are used for Select, Insert, Update and Delete operations. The following image is an example :

After choosing all your methods, click Finish to close this dialog. If you are going to let the ObjectDataSource handle the paging operation, go to your page's source code, find the code of GridView control and remove the SelectParameters. This is necessary because startRowIndex and maximumRows will be provided by ObjectDataSource control. If you do not remove them, you will get an error message.

In order to activate paging in ObejctDataSource, you have to set its EnablePaging property to True. you also have to set the AllowPaging property of your GridView control to true. In order for ObjectDataSource to do paging operation correctly, we have to tell it how many records are in database. Therefore, there must be a public method in our business class that return the total number of rows in DB. What we need is to assign it's name to SelectCountMethod property of ObjectDataSource. You do not need to flag this property with an attribute:

public int GetTotalRecordCount()
{
return innerDAL.GetTotalRecordCount();
}

Notice that if you are filtering the results of your SelectMethod, for example by passing a filter string to it, you have to perform the same filter on the result of SelectCountMethod.

Now build and run your website. you will see that the data is being shown and the grid supports sorting and paging very well. To ensure that paging is working correctly, run Microsoft Sql Server Profiler, and check to see if the Select SQL statement has correct startRowIndex and maximumRowCount values.

To insert a new record, you may create a new entity (i.e. PersonEntity) , fill it and save it to DB.

To update a record, retrieve the record from database using it's Primary Key, edit it and save it back to db.

To delete a record, perform a delete operation on database using the records PK.

But how to obtain the record's Primary Key? You may save it somewhere in UI when the UI control is getting bound. To do this, I usually write such a code in RowDataBound event :

if (e.Row.RowType == DataControlRowType.DataRow)
{
int Serial = DataBinder.Eval(e.Row.DataItem, "Serial");
e.Row.Cells[0].Attributes.Add("Serial", Serial.ToString());
}

In the above code, if the row being bound is a data row (not footer or header), we get the value of "Serial" column and store it in the 1st cell of the current row. Notice that whatever toy add yo .Attributes collection will be available to the rendered html page. Thus, never save passwords or other sort of crucial data with this method.

Now, for each row, you have the Primary Key value. Therefore, we may perform update and delete operations easily. Not keeping the whole data in memory (or in ViewState), increases the access to data base, but reduces the usage of server's resources. However, it is up to you and your project's conditions to decide that method should be used.

You may download a full example of this implementation HERE. Please note that the file is password protected and it's password is : aspguy.wordpress.com

Bye for now..

]]> http://banditoplus.wordpress.com/?p=14 Mon, 21 Jul 2008 21:33:12 +0000 banditoplus http://banditoplus.wordpress.com/?p=14 Today I realised working with IDataReader can be a real pain. First of all you can't actually check if a column actually exists before accessing a field. You simply get an IndexOutOfRange Exception. You can't even test if its null.

No Exception

One way to solve this problem is to use the property FieldCount and method GetName.

IDataReader reader = [MyDataSource];
List<string> header = new List<string>( );
for (int i = 0; i < reader.FieldCount; ++i)
{
   header.Add(reader.GetName(i));
}

Now you can check if the column exists by looking for it in the list.
if( header.Contains( "MyColumnName" ))
{ ... }

DBNull != null

The next problem is that the return value might be DBNull. Unluckily DBNull isn't null, so you can't use the practical ?? operator. So this will not work:

int x = (int)(reader["MyInt"] ?? 0);

What would be possible is this:

int x = reader.IsDBNull( reader.GetOrdinal( "MyInt" ) ) ? (int) reader["MyInt"] : 0;

But that's just awful.

Generic Method

OK, my first attempt to solve both problems was a simple utility method.

protected T GetValue<T>(IDataReader reader, List<string> header, string fieldname)
{
 T result = default(T);
 if (header.Contains(fieldname))
 {
  if (reader[fieldname] != Convert.DBNull)
  {
   result = (T)reader[fieldname];
  }
 }
 return result;
}

This generic method gets the current reader instance, the header list from before and the name of the field as parameter. T is the column type. default(T) sets the default value of the type, so null for objects and 0 (int) for value types. We then run both tests and finally cast the value.
A method call would look something like this:

int x = GetValue<int>(reader, header, "MyInt");

That does actually work, but I hate the idea of sending the reader and header in each call. So the next step is wrapping everything up in a class.

Generice DataReader Class

public class GenericDataReader
{
 private IDataReader reader;
 private List<string> header = new List<string>();

 public object this[int i]
 {
  get{ return reader[i]; }
 }
}

The class is fairly simple and wraps the IDataReader functionality quite nicely. As you can see the Read() method returns false if the IDataReader is null. One thing less to worry about when looping through the data. The indexer at the end of the class allows you to access the reader directly if necessary.

Last example for today:

IDataReader reader = [MyDataSource];
GenericDataReader g = new GenericDataReader(reader);
while(g.Read( ))
{
 int x = g.GetValue<int>("MyInt");
}
g.Close( );

Now IDataReader should be a little more tame.

Firstly, in the DataAccessLayerBase namespace, we declare a public enum type named ProviderType:

public enum ProviderType
{
SqlServer,
Odbc,
OleDb
}

We also remove the ProviderName property from DALHelper class, and instead, add a new internal method, as bellow, to get a string representation of each ProviderType member:

internal static string GetProviderTypeName(ProviderType providerType)
{
switch (providerType)
{
case ProviderType.SqlServer: return "System.Data.SqlClient";
case ProviderType.Odbc: return "System.Data.Odbc";
case ProviderType.OleDb: return "System.Data.OleDb";
default: return "System.Data.SqlClient";
}
}
The custom attribute we need for specifying the provider type, must have a public property of type ProviderType. We also add a constructor, with a positional parameter of type ProviderType, to our custom attribute class:

[AttributeUsage(AttributeTargets.Class)]
public sealed class DbProviderTypeAttribute : Attribute
{
public ProviderType PrType
{
set;
get;
}
}

The AttributeUsage attribute indicates that this custom attribute can be applied to classes only.

To make this attribute effective, we need to alter the base DAL class's constructor as bellow:

first we must check to see if the DbProviderTypeAttribute attribute has been applied to the derived DAL class:

if (!this.GetType().IsDefined(typeof(DbProviderTypeAttribute), false))
throw new System.Exception("DbProviderTypeAttribute must be applied to DAL class");

The above code examines the existence of DbProviderTypeAttribute and throws an exception of it does not exist.

Then, the following piece of code, extracts the instance of DbProviderTypeAttribute from the class's metadata, and uses the value of it's PrType property to set the ProviderName :

List<object> t = this.GetType().GetCustomAttributes(typeof(DbProviderTypeAttribute), false).ToList();
DbProviderTypeAttribute Provider = t[0] as DbProviderTypeAttribute;
ProviderName = DALHelper.GetProviderTypeName(Provider.PrType);
_ProviderFactory = DbProviderFactories.GetFactory(ProviderName);

That's it. This way we have reduced the coupling between our UI (web.config file) and the DAL class. When developing a derived DAL class, we have to apply DbProviderType attribute to it:

[DbProviderType(PrType=ProviderType.SqlServer)]
public class PersonDAL : DALBase
{ ...

Implementing the business classes

The implementation of business classes are fairly easy. A business class is a bridge between the presentation layer and the data access layer, perform business checks, controls concurrencies and even might control the business transactions.

The business classes can be either static or instance classes. Each business method can create one or more instances of the required DAL classes. However, since each DAL class has it's own connection object (innerConnection property), system transactions would better be controlled in business methods. This may even solve the issue that is raised when a layered architecture needs to control both business and system transactions.

The easiest way to control the transactions, is using System.Transaction name space and TransactionScope class. The illustration of TransactionScope requires an indipendent post, but for now, lets say that transaction begins when an instance of TransactionScope class is created and it is commited when the .Complete() method is called:

using (TransactionScope scope = new TransactionScope())

{

.....

scope.Complete();

}

if an exception is thrown, the transaction will roll back :

using (TransactionScope scope = new TransactionScope())

{

PersonDAL PDAL= new PersonDAL();

....

ChildDAL CDAL= new ChildDAL();

...

PDAL.Update(personDT);

CDAL.Update(childDT);

scope.Complete();

}

Note that MSDTC service must be running on the server machine.

so far, the definition of business classes requires no additional settings. however, when developing the presentaion layer, we will come back and make some minor changes to make our bisuness classes compatible with UI components.

A sample business class might look like this:

public class PersonBiz
{

private PersonDAL innerDAL = new PersonDAL();
public DataTable FetchAll(int startRowIndex, int maximumRows)
{
PersonEntity entity = new PersonEntity();
innerDAL.Fill(entity, startRowIndex, maximumRows);
return entity;
}

public void Update(System.Data.DataTable table)
{
// validate fields/perform business checks and throw an exception if a criteria is not met
innerDAL.Update(table);
}
:

:

}

]]> http://pythonyan.wordpress.com/?p=238 Wed, 16 Jul 2008 09:44:55 +0000 pythonyan http://pythonyan.wordpress.com/?p=238 Come postato da Minerva al seguente link è possibile leggere alcune differenze tra l'approccio Linq To Sql e Ado.Net.Molto interessante e .. istruttivo.

For doing this, we may define the Fill method virtual and each DAL class may override it to fetch records based on startRowIndex and RowCount from the data base. The 2nd way is to assume that every SelectCommand has two paramerers names startRowIndex and RowCount! This means that we always must supply two int parameters to Fill method. I propose you to have several overloaded Fill methods to use a proper one in different occasions.

Anyway, if we suppose that every SelectCommand executes a stored procedure having two int parameters, we might change the Fill method (or develop an overloaded one) this way:

public void Fill(DataTable table, int startRowIndex, int RowCount)
{
DbParameter p;
innerAdapter.SelectCommand.Parameters.Clear();

p = ProviderFactory.CreateParameter();
p.ParameterName = "StartIndex";
p.Value = startRowIndex;
innerAdapter.SelectCommand.Parameters.Add(p);

p = ProviderFactory.CreateParameter();
p.ParameterName = "RowCount";
p.Value = RowCount;
innerAdapter.SelectCommand.Parameters.Add(p);
if (table.Rows.Count > 0)
table.Rows.Clear();
innerAdapter.Fill(table);
}

This Fill method adds two parameters to SelectCommand property of the innerAdapter, fills the DataTable by calling the innerAdapter.Fill method. Notice that we must clear up the DataTable because the innerAdapter.Fill method will append new records to the DataTable if any records exists in it.

But how to implement the paging? The answer might differ fro different data bases. However, I will provide a simple method for SQL Server 2005. SQL Server 2005 provides Ranking funtions, i.e. Row_Number() funtion, so that we may easily rank the resulting records of each table. For more information about Row_number function, please check out the SQL Server 2005 Books Online or MSDN.

Anyway, for our sample database, I have written a stored procedure named FetchAllPerson which has two int parameters, called @StartIndex and @RowCount:

create procedure FetchAllPerson
@StartIndex int,
@RowCount int
As

with NoFilterRecords
as
(
Select Row_Number() over (order by Serial) as RIndex , Serial, FirstName, LastName from Person
)
Select * from NoFilterRecords where RIndex>=@StartIndex and RIndex <@StartIndex+@RowCount
order by 1
Go

This procedure first ranks all records, then fetch only those records positioned in the specific range. Therefore, the innerAdapter.SelectCommand.CommandType must be set to CommandType .StoredProcedure .

innerAdapter.SelectCommand.CommandText = "FetchAllPerson";
innerAdapter.SelectCommand.CommandType = System.Data.CommandType.StoredProcedure;

Working with identity fields

The value of Identity fields is generated automatically. Therefore, a new row in a DataTable, may not have a value for its Identity fields or their value may not be identical to the mapping record in database after the record is inserted. Thus, we have to reflect the new value of Identity fields to the related row inside the DataTable. For doing this, add a Select statement to the end of Insert statements and seperate them with a semi colon :

innerAdapter.InsertCommand.CommandText = "Insert into Person (Serial, FirstName, LastName) \n" +
"Values (@Serial, @FirstName, @LastName); \n" +
"Select * from Person where Serial = SCOPE_IDENTITY()";

The Select statement will fetch the new record from database and reflect any changes to the inserted row. To make this method work, we must set the UpdatedRowSource property to FirstReturnedRecord:

innerAdapter.InsertCommand.UpdatedRowSource = System.Data.UpdateRowSource.FirstReturnedRecord;

This may be done in the base DAL class. This setting will fetch one record and will synchronize the inserted row with the data base. The SCOPE_IDENTITY() funtion returns the last identity value assigned to a field. This works in SQL SERVER only and you must perform a similar task for other data bases.

Ok this is all about the Data Access Layer. We will discuss about the business layer on the next post.

]]> http://scriptforall.wordpress.com/?p=27 Tue, 15 Jul 2008 11:42:54 +0000 kostland http://scriptforall.wordpress.com/?p=27 where timerticlickvoid is the click of the timer....

public void timertickvoid()
{
// Set the timer interval to 5 minutes
timerCheck.Interval = (int)(5 * 1000 * 60);

FileStream fs = File.OpenRead("timer.log");
StreamReader sr = new StreamReader(fs);
string myInput = sr.ReadToEnd();
sr.Close();
fs.Close();

DateTime dtFile = Convert.ToDateTime(myInput);

DateTime dt2 = DateTime.Now;

TimeSpan span = dt2.Subtract(dtFile);
int dif = span.Days*60*24 + span.Hours*60+span.Minutes;
if (dif > 5)//>60
{
RunRoutines();
}

}