Mega Code Archive
Define Table relation and load combined data into DataGrid
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Imports System
Imports System.Drawing
Imports System.Collections
Imports System.ComponentModel
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.ComponentModel.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.CommandText = "Select * from Employees"
myCommand2 = New System.Data.SqlClient.SqlCommand( )
myCommand2.Connection = myConnection
myCommand2.CommandText = "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.components = New System.ComponentModel.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
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