в 16:40, 26 мая 2010

2010-05-26T16:40:06Z

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2010-05-26T12:44:46Z

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==DataRelation: Create a relation between the two tables==

<source lang="vbnet">
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

</source>

==Define Table relation and load combined data into DataGrid==

<source lang="vbnet">
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

</source>

==Relational Data Navigation==

<source lang="vbnet">
Imports System.Data.SqlClient
Imports System.Windows.Forms
<Global.Microsoft.VisualBasic.rupilerServices.DesignerGenerated()> _
Partial Class Relation
Inherits System.Windows.Forms.Form
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.cmdClear = New System.Windows.Forms.Button
Me.cmdFill = New System.Windows.Forms.Button
Me.lstOrder = New System.Windows.Forms.ListBox
Me.SuspendLayout()
"
"cmdClear
"
Me.cmdClear.Anchor = CType((System.Windows.Forms.AnchorStyles.Bottom Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
Me.cmdClear.Location = New System.Drawing.Point(210, 238)
Me.cmdClear.Name = "cmdClear"
Me.cmdClear.Size = New System.Drawing.Size(72, 24)
Me.cmdClear.TabIndex = 5
Me.cmdClear.Text = "Clear"
"
"cmdFill
"
Me.cmdFill.Anchor = CType((System.Windows.Forms.AnchorStyles.Bottom Or System.Windows.Forms.AnchorStyles.Left), System.Windows.Forms.AnchorStyles)
Me.cmdFill.Location = New System.Drawing.Point(10, 238)
Me.cmdFill.Name = "cmdFill"
Me.cmdFill.Size = New System.Drawing.Size(72, 24)
Me.cmdFill.TabIndex = 4
Me.cmdFill.Text = "Fill"
"
"lstOrder
"
Me.lstOrder.Anchor = CType((((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Bottom) _
Or System.Windows.Forms.AnchorStyles.Left) _
Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
Me.lstOrder.IntegralHeight = False
Me.lstOrder.Location = New System.Drawing.Point(10, 3)
Me.lstOrder.Name = "lstOrder"
Me.lstOrder.Size = New System.Drawing.Size(272, 229)
Me.lstOrder.TabIndex = 3
"
"Relation
"
Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.ClientSize = New System.Drawing.Size(292, 267)
Me.Controls.Add(Me.cmdClear)
Me.Controls.Add(Me.cmdFill)
Me.Controls.Add(Me.lstOrder)
Me.Font = New System.Drawing.Font("Tahoma", 8.25!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
Me.Name = "Relation"
Me.Text = "Relation"
Me.ResumeLayout(False)
End Sub
Friend WithEvents cmdClear As System.Windows.Forms.Button
Friend WithEvents cmdFill As System.Windows.Forms.Button
Friend WithEvents lstOrder As System.Windows.Forms.ListBox
Private Sub cmdFill_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdFill.Click
Dim Connect As String = "Data Source=localhost;Integrated Security=True;Initial Catalog=Northwind;"
Dim con As New SqlConnection(Connect)
Dim SQL As String = "SELECT * FROM Orders "
Dim cmd As New SqlCommand(SQL, con)
Dim adapter As New SqlDataAdapter(cmd)
Dim dsNorthwind As New DataSet()
con.Open()
adapter.Fill(dsNorthwind, "Orders")
cmd.rumandText = "SELECT * FROM Customers"
adapter.Fill(dsNorthwind, "Customers")
cmd.rumandText = "SELECT * FROM Employees"
adapter.Fill(dsNorthwind, "Employees")
con.Close()
Dim relCustomersOrders As New DataRelation("CustomersOrders", _
dsNorthwind.Tables("Customers").Columns("CustomerID"), _
dsNorthwind.Tables("Orders").Columns("CustomerID"))
dsNorthwind.Relations.Add(relCustomersOrders)
Dim rowParent, rowChild As DataRow
For Each rowParent In dsNorthwind.Tables("Customers").Rows
For Each rowChild In rowParent.GetChildRows(relCustomersOrders)
lstOrder.Items.Add(rowParent("CompanyName") & _
" ordered on " & rowChild("OrderDate"))
Next
Next
End Sub
Private Sub cmdClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdClear.Click
lstOrder.Items.Clear()
End Sub
End Class

</source>

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VB.Net/Database ADO.net/Table Relation - История изменений

в 16:40, 26 мая 2010

Admin: 1 версия