Imports System
Imports System.Collections
Imports System.Data
Imports System.IO
Imports System.Xml.Serialization
Imports System.Xml
Imports System.Windows.Forms
Imports System.Data.SqlClient
Imports System.Data.OleDb
Public Class MainClass
Shared Sub Main()
Dim form1 As Form = New Form1
Application.Run(form1)
End Sub
End Class
Public Class Form1
Inherits System.Windows.Forms.Form
#Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
'This call is required by the Windows Form Designer.
InitializeComponent()
'Add any initialization after the InitializeComponent() call
End Sub
'Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer
'NOTE: The following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
Friend WithEvents button1 As System.Windows.Forms.Button
Private Sub InitializeComponent()
Me.button1 = New System.Windows.Forms.Button()
Me.SuspendLayout()
'
'button1
'
Me.button1.Font = New System.Drawing.Font("Microsoft Sans Serif", 9.75!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
Me.button1.Location = New System.Drawing.Point(10, 8)
Me.button1.Name = "button1"
Me.button1.Size = New System.Drawing.Size(240, 64)
Me.button1.TabIndex = 1
Me.button1.Text = "Update a record"
'
'Form1
'
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(260, 81)
Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.button1})
Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
Me.MaximizeBox = False
Me.MinimizeBox = False
Me.Name = "Form1"
Me.Text = "Row Updating"
Me.ResumeLayout(False)
End Sub
#End Region
Dim dbConn As New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI")
Dim WithEvents da As New SqlDataAdapter("SELECT ID, FirstName, LastName FROM Employee", dbConn)
Private Sub button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles button1.Click
Dim cb As New SqlCommandBuilder(da)
Dim ds As New DataSet("Employee")
da.Fill(ds)
ds.Tables(0).Rows(0)("ID") = "1"
da.Update(ds.GetChanges())
End Sub
Private Sub da_RowUpdating(ByVal sender As Object, _
ByVal e As SqlRowUpdatingEventArgs) _
Handles da.RowUpdating
' Only perform processing if this is an UPDATE statement
If (e.StatementType = StatementType.Update) Then
' Check that the original record is not changed
Dim strSQL As String = "SELECT ID, FirstName, LastName " & _
"FROM Employee WHERE "
strSQL &= "ID='" & e.Row("ID", DataRowVersion.Original)
strSQL &= "' AND "
strSQL &= "FirstName='" & e.Row("FirstName", DataRowVersion.Original)
strSQL &= "' AND "
strSQL &= "LastName='" & e.Row("LastName", DataRowVersion.Original) & "'"
' Open the connection
dbConn.Open()
' Create a command to retrieve the number of records affected
Dim cmm As New SqlCommand(strSQL, dbConn)
' If the number of records retrieved is zero, the record has changed
If (cmm.ExecuteNonQuery() = 0) Then
' Display the confirm message
If (MessageBox.Show("The record you are attempting to modify has " & _
"already changed by another user. Do you " & _
"want to overwrite it?", "Update", _
MessageBoxButtons.YesNo) = DialogResult.No) Then
' Skip the update for the current row
e.Status = UpdateStatus.SkipCurrentRow
End If
End If
' Close the connection
dbConn.Close()
End If
End Sub
End Class