VB.Net/Database ADO.net/Sql Data Adapter

Материал из VB Эксперт
Перейти к: навигация, поиск

Set SqlDataAdapter Update Batch Size

Imports System
Imports System.Data
Imports System.Windows.Forms
Imports System.Data.SqlClient
Imports System.IO
public class MainClass
   Shared Sub Main()
      Dim form1 As Form = New Form1
   End Sub
End Class
Public Class Form1
   Inherits System.Windows.Forms.Form
   Private cb As SqlCommandBuilder
   Private da As SqlDataAdapter
#Region " Windows Form Designer generated code "
   Public Sub New()
      "This call is required by the Windows Form Designer.
      "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
         End If
      End If
   End Sub
   "Required by the Windows Form Designer
   Private components As System.ruponentModel.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 DataGrid1 As System.Windows.Forms.DataGrid
   Friend WithEvents buttonUpdate As System.Windows.Forms.Button
   Friend WithEvents DataSet1 As System.Data.DataSet
   Friend WithEvents SqlCommand1 As System.Data.SqlClient.SqlCommand
   <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
      Me.DataGrid1 = New System.Windows.Forms.DataGrid
      Me.buttonUpdate = New System.Windows.Forms.Button
      Me.DataSet1 = New System.Data.DataSet
      Me.SqlCommand1 = New System.Data.SqlClient.SqlCommand
      CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).BeginInit()
      CType(Me.DataSet1, System.ruponentModel.ISupportInitialize).BeginInit()
      Me.DataGrid1.DataMember = ""
      Me.DataGrid1.HeaderForeColor = System.Drawing.SystemColors.ControlText
      Me.DataGrid1.Location = New System.Drawing.Point(8, 8)
      Me.DataGrid1.Name = "DataGrid1"
      Me.DataGrid1.Size = New System.Drawing.Size(400, 192)
      Me.DataGrid1.TabIndex = 0
      Me.buttonUpdate.Location = New System.Drawing.Point(171, 208)
      Me.buttonUpdate.Name = "buttonUpdate"
      Me.buttonUpdate.TabIndex = 1
      Me.buttonUpdate.Text = "Update"
      Me.DataSet1.DataSetName = "NewDataSet"
      Me.DataSet1.Locale = New System.Globalization.CultureInfo("en-GB")
      Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
      Me.ClientSize = New System.Drawing.Size(416, 245)
      Me.Name = "Form1"
      Me.Text = "Form1"
      CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).EndInit()
      CType(Me.DataSet1, System.ruponentModel.ISupportInitialize).EndInit()
   End Sub
#End Region
   Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
      "Create Connection object
      Dim thisConnection As New SqlConnection("server=(local)\SQLEXPRESS;" & _
          "integrated security=sspi;database=MyDatabase")
      " Sql Query
      Dim sql As String = "SELECT * FROM Employee"
      " Create a Command
      SqlCommand1 = New SqlCommand(sql, thisConnection)
      " Create SqlDataAdapter
      da = New SqlDataAdapter
      da.SelectCommand = SqlCommand1
      " Create SqlCommandBuilder object
      cb = New SqlCommandBuilder(da)
      " Fill Dataset
      da.Fill(DataSet1, "Employee")
      " Bind the data to the grid at runtime
      DataGrid1.SetDataBinding(DataSet1, "Employee")
   End Sub
   Private Sub buttonUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonUpdate.Click
      da.UpdateBatchSize = 10
      da.Update(DataSet1, "Employee")
   End Sub
End Class

SqlDataAdapter Event: updated and updating

Imports System
Imports System.Data
Imports System.Data.SqlClient

public class MainClass
   Shared Sub Main()
      Dim thisConnection As New SqlConnection("server=(local)\SQLEXPRESS;" & _
          "integrated security=sspi;database=MyDatabase")
      Dim sql As String = "SELECT FirstName, LastName From Employee"
         Dim thisAdapter As New SqlDataAdapter(sql, thisConnection)
         Dim cb As New SqlCommandBuilder(thisAdapter)
         Dim ds As New DataSet
         thisAdapter.Fill(ds, 0, 1, "Customers")
         AddHandler thisAdapter.RowUpdating, AddressOf OnRowUpdating
         AddHandler thisAdapter.RowUpdated, AddressOf OnRowUpdated
         Dim dt As DataTable = ds.Tables("Customers")
         dt.Rows(0)(1) = "The Volcano Corporation"
         thisAdapter.Update(ds, "Customers")
         RemoveHandler thisAdapter.RowUpdating, AddressOf OnRowUpdating
         RemoveHandler thisAdapter.RowUpdated, AddressOf OnRowUpdated
      Catch ex As SqlException
         " Close Connection
      End Try
   End Sub
   " Handler for OnRowUpdating
   Shared Private Sub OnRowUpdating(ByVal sender As Object, ByVal e As SqlRowUpdatingEventArgs)
      Console.WriteLine("OnRowUpdating Event")
      If Not e.Status = UpdateStatus.Continue Then
         Console.WriteLine("RowStatus = " & e.Status.ToString())
      End If
   End Sub
   " Handler for OnRowUpdated
   Shared Private Sub OnRowUpdated(ByVal sender As Object, ByVal e As SqlRowUpdatedEventArgs)
      Console.WriteLine("OnRowUpdated Event")
      Console.WriteLine("Records Affected = " & e.RecordsAffected.ToString())
   End Sub
End Class