VB.Net by API/System.Data.SqlClient/SqlDataAdapter

Материал из VB Эксперт
Версия от 12:50, 26 мая 2010; Admin (обсуждение | вклад) (1 версия)
(разн.) ← Предыдущая | Текущая версия (разн.) | Следующая → (разн.)
Перейти к: навигация, поиск

SqlDataAdapter.FillSchema

  

Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Data.SqlClient
Imports System.Collections
Imports System.Data

Public Class MainClass
    
    Shared Sub Main()
        Dim da As New SqlDataAdapter( _
                   "SELECT ID, FirstName, LastName FROM Employee", _
                   "Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI")
        Dim ds As New DataSet("Employee")
        da.FillSchema(ds, SchemaType.Source)
        ds.ReadXml("Employee.xml")
        Dim Table As DataTable = ds.Tables(0)
        Dim numCols As Integer = Table.Columns.Count
        Dim Row As DataRow
        For Each Row In Table.Rows
            Dim i As Integer
            For i = 0 To numCols - 1
                Console.WriteLine(Table.Columns(i).ColumnName & " = " & Row(i))
            Next
            Console.WriteLine()
        Next
    End Sub
End Class


SqlDataAdapter.ReadXml

  

Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO
Imports System.Data.SqlClient
Imports System.Collections
Imports System.Data

Public Class MainClass
    
    Shared Sub Main()
        Dim da As New SqlDataAdapter( _
                   "SELECT ID, FirstName, LastName FROM Employee", _
                   "Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI")
        Dim ds As New DataSet("Employee")
        da.FillSchema(ds, SchemaType.Source)
        ds.ReadXml("Employee.xml")
        Dim Table As DataTable = ds.Tables(0)
        Dim numCols As Integer = Table.Columns.Count
        Dim Row As DataRow
        For Each Row In Table.Rows
            Dim i As Integer
            For i = 0 To numCols - 1
                Console.WriteLine(Table.Columns(i).ColumnName & " = " & Row(i))
            Next
            Console.WriteLine()
        Next
    End Sub
End Class


SqlDataAdapter.RowUpdated

  
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"
      Try
         thisConnection.Open()
         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
         Console.WriteLine(ex.Message)
      Finally
         " Close Connection
         thisConnection.Close()
      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


SqlDataAdapter.RowUpdating

  
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"
      Try
         thisConnection.Open()
         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
         Console.WriteLine(ex.Message)
      Finally
         " Close Connection
         thisConnection.Close()
      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


SqlDataAdapter.SelectCommand

  
 Imports System
 Imports System.Drawing
 Imports System.Collections
 Imports System.ruponentModel
 Imports System.Windows.Forms
 Imports System.Data
 Imports System.Data.SqlClient
 
Public Class MainClass
    Shared Sub Main(  )
        Application.Run(New ADOForm1() )
    End Sub
   
End Class
  Public Class ADOForm1
     Inherits System.Windows.Forms.Form
     Friend WithEvents DataGrid1 As System.Windows.Forms.DataGrid
     Private components As System.ruponentModel.Container
     " private System.Data.ADO.ADOConnection myConnection;
     Private myConnection As System.Data.SqlClient.SqlConnection
     Private myDataSet As System.Data.DataSet
     Private myCommand As System.Data.SqlClient.SqlCommand
     Private myCommand2 As System.Data.SqlClient.SqlCommand
     Private myDataAdapter As System.Data.SqlClient.SqlDataAdapter
     Private myDataAdapter2 As System.Data.SqlClient.SqlDataAdapter
     Public Sub New(  )
         InitializeComponent(  )
         " create the connection object and open it
         Dim connectionString As String = _
             "server=localhost; uid=sa; " & _
             "pwd=YourPassword; database=northwind"
         myConnection = _
         New System.Data.SqlClient.SqlConnection(connectionString)
         myConnection.Open(  )
         " create the DataSet and set a property
         myDataSet = New System.Data.DataSet(  )
         myDataSet.CaseSensitive = True
         " create the SqlCommand  object and assign the
         " connection and the select statement
         myCommand = New System.Data.SqlClient.SqlCommand(  )
         myCommand.Connection = myConnection
         myCommand.rumandText = "Select * from Employees"
         myCommand2 = New System.Data.SqlClient.SqlCommand(  )
         myCommand2.Connection = myConnection
         myCommand2.rumandText = "Select * from Orders"
         " create the myDataAdapter object and pass in the
         " SQL Command object and establish the table mappings
         myDataAdapter = New System.Data.SqlClient.SqlDataAdapter(  )
         myDataAdapter2 = New System.Data.SqlClient.SqlDataAdapter(  )
         myDataAdapter.SelectCommand = myCommand
         myDataAdapter2.SelectCommand = myCommand2
         myDataAdapter.TableMappings.Add("Table", "Employees")
         myDataAdapter2.TableMappings.Add("Table", "Orders")
         " Tell the myDataAdapter object to fill the DataSet
         myDataAdapter.Fill(myDataSet)
         myDataAdapter2.Fill(myDataSet)
         Dim myDataRelation As System.Data.DataRelation
         Dim dataColumn1 As System.Data.DataColumn
         Dim dataColumn2 As System.Data.DataColumn
         dataColumn1 = _
             myDataSet.Tables("Employees").Columns("EmployeeID")
         dataColumn2 = _
             myDataSet.Tables("Orders").Columns("EmployeeID")
         myDataRelation = New System.Data.DataRelation( _
             "EmployeesToOrders", dataColumn1, dataColumn2)
         myDataSet.Relations.Add(myDataRelation)
         Dim dataSetView As DataViewManager = _
             myDataSet.DefaultViewManager
         " display it in the grid
         DataGrid1.DataSource = _
             dataSetView
         DataGrid1.DataMember = "Employees"
     End Sub "New
     Private Sub InitializeComponent(  )
         Me.ruponents = New System.ruponentModel.Container(  )
         Me.dataGrid1 = New System.Windows.Forms.DataGrid(  )
         dataGrid1.Location = New System.Drawing.Point(48, 24)
         dataGrid1.Size = New System.Drawing.Size(368, 160)
         dataGrid1.TabIndex = 0
         Me.Text = "ADOFrm1"
         Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
         Me.ClientSize = New System.Drawing.Size(464, 273)
         Me.Controls.Add(dataGrid1)
     End Sub 
 End Class


SqlDataAdapter.TableMappings.Add

  
Imports System
Imports System.Data
Imports System.Windows.Forms
Imports System.Data.SqlClient
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.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 DataSet1 As System.Data.DataSet
   <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
      Me.DataGrid1 = New System.Windows.Forms.DataGrid
      Me.DataSet1 = New System.Data.DataSet
      CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).BeginInit()
      CType(Me.DataSet1, System.ruponentModel.ISupportInitialize).BeginInit()
      Me.SuspendLayout()
      "
      "DataGrid1
      "
      Me.DataGrid1.DataMember = ""
      Me.DataGrid1.HeaderForeColor = System.Drawing.SystemColors.ControlText
      Me.DataGrid1.Location = New System.Drawing.Point(0, 0)
      Me.DataGrid1.Name = "DataGrid1"
      Me.DataGrid1.Size = New System.Drawing.Size(416, 224)
      Me.DataGrid1.TabIndex = 0
      "
      "DataSet1
      "
      Me.DataSet1.DataSetName = "NewDataSet"
      Me.DataSet1.Locale = New System.Globalization.CultureInfo("en-GB")
      "
      "Form1
      "
      Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
      Me.ClientSize = New System.Drawing.Size(408, 221)
      Me.Controls.Add(Me.DataGrid1)
      Me.Name = "Form1"
      Me.Text = "Form1"
      CType(Me.DataGrid1, System.ruponentModel.ISupportInitialize).EndInit()
      CType(Me.DataSet1, System.ruponentModel.ISupportInitialize).EndInit()
      Me.ResumeLayout(False)
   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 Queries 
      Dim sql1 As String = _
         "SELECT * FROM Employee; "
      Dim sql2 As String = _
         "SELECT * FROM Employee"
      Dim sql As String = sql1 & sql2
      " Create Data Adapter
      Dim da As New SqlDataAdapter(sql, thisConnection)
      " Map Default table names to Employees and Orders
      da.TableMappings.Add("Table", "Employee")
      da.TableMappings.Add("Table1", "Employee")
      " Fill Dataset
      da.Fill(DataSet1)
      " Create a relation between the two tables
      "Dim dr As New DataRelation( _
      "   "EmployeeOrder", _
      "   DataSet1.Tables(0).Columns("ID"), _
      "   DataSet1.Tables(1).Columns("ID"))
      "DataSet1.Relations.Add(dr)
      " Bind the data to the grid at runtime
      DataGrid1.SetDataBinding(DataSet1, "Employee")
   End Sub
End Class


SqlDataAdapter.WriteXml

  
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")
      " Sql Query 
      Dim sql As String = _
         "SELECT * FROM Employee"
      Try
         " Create Data Adapter
         Dim da As New SqlDataAdapter
         da.SelectCommand = New SqlCommand(sql, thisConnection)
         " Create and fill Dataset
         Dim ds As New DataSet
         da.Fill(ds, "Employee")
         " Extract DataSet to XML file
         ds.WriteXml("Employee.xml")
      Catch ex As SqlException
         " Display error
         Console.WriteLine("Error: " & ex.ToString())
      Finally
         " Close Connection
         thisConnection.Close()
         Console.WriteLine("Connection Closed")
      End Try
   End Sub
End Class