VB.Net Tutorial/Database ADO.net/Data binding

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Bind DataTable to Control

<source lang="vbnet">Imports System.Data Imports System.Data.OleDb Imports System.Windows.Forms public class BindDataTableToControl

  public Shared Sub Main
       Application.Run(New Form1)
  End Sub

End class

Public Class Form1

   " The data source.
   Private m_ContactsTable As DataTable
   " The data source"s CurrencyManager.
   Private m_CurrencyManager As CurrencyManager
   Private Sub Form1_Load(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles MyBase.Load
       " Make a DataTable.
       m_ContactsTable = New DataTable("Contacts")
       " Add columns.
       m_ContactsTable.Columns.Add("FirstName", GetType(String))
       m_ContactsTable.Columns.Add("LastName", GetType(String))
       m_ContactsTable.Columns.Add("Street", GetType(String))
       m_ContactsTable.Columns.Add("City", GetType(String))
       m_ContactsTable.Columns.Add("State", GetType(String))
       m_ContactsTable.Columns.Add("Zip", GetType(String))
       " Make the combined FirstName/LastName unique.
       Dim first_last_columns() As DataColumn = { _
           m_ContactsTable.Columns("FirstName"), _
           m_ContactsTable.Columns("LastName") _
       }
       m_ContactsTable.Constraints.Add( _
           New UniqueConstraint(first_last_columns))
       " Make some contact data.
       m_ContactsTable.Rows.Add(New Object() {"A", "B","C", "D", "E", "11111"})
       m_ContactsTable.Rows.Add(New Object() {"F", "G","H", "I", "J", "22222"})
       m_ContactsTable.Rows.Add(New Object() {"K", "L","M", "N", "O", "33333"})
       m_ContactsTable.Rows.Add(New Object() {"P", "Q","R", "S", "T", "44444"})
       m_ContactsTable.Rows.Add(New Object() {"U", "V","W", "X", "Y", "55555"})
       m_ContactsTable.Rows.Add(New Object() {"Z", "A","B", "C", "D", "66666"})
       m_ContactsTable.Rows.Add(New Object() {"E", "F","G", "H", "I", "77777"})
       m_ContactsTable.Rows.Add(New Object() {"J", "K","L", "M", "N", "88888"})
       " Bind to controls.
       txtFirstName.DataBindings.Add("Text", m_ContactsTable, "FirstName")
       txtLastName.DataBindings.Add("Text", m_ContactsTable, "LastName")
       txtStreet.DataBindings.Add("Text", m_ContactsTable, "Street")
       txtCity.DataBindings.Add("Text", m_ContactsTable, "City")
       txtState.DataBindings.Add("Text", m_ContactsTable, "State")
       txtZip.DataBindings.Add("Text", m_ContactsTable, "Zip")
       " Save a reference to the CurrencyManager.
       m_CurrencyManager = _
           DirectCast(Me.BindingContext(m_ContactsTable), CurrencyManager)
   End Sub
   Private Sub btnFirst_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles btnFirst.Click
       m_CurrencyManager.Position = 0
   End Sub
   Private Sub btnPrev_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles btnPrev.Click
       m_CurrencyManager.Position -= 1
   End Sub
   Private Sub btnNext_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles btnNext.Click
       m_CurrencyManager.Position += 1
   End Sub
   Private Sub btnLast_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles btnLast.Click
       m_CurrencyManager.Position = m_CurrencyManager.Count - 1
   End Sub
   " Add a new record.
   Private Sub btnAdd_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles btnAdd.Click
       m_CurrencyManager.AddNew()
   End Sub
   Private Sub btnDelete_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles btnDelete.Click
       If MsgBox("Are you sure you want to delete this record?", _
           MsgBoxStyle.Question Or MsgBoxStyle.YesNo, _
           "Confirm Delete?") = MsgBoxResult.Yes _
       Then
           m_CurrencyManager.RemoveAt(m_CurrencyManager.Position)
       End If
   End Sub

End Class <Global.Microsoft.VisualBasic.rupilerServices.DesignerGenerated()> _ Partial Public Class Form1

   Inherits System.Windows.Forms.Form
   "Form overrides dispose to clean up the component list.
   <System.Diagnostics.DebuggerNonUserCode()> _
   Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
       If disposing AndAlso components IsNot Nothing Then
           components.Dispose()
       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.
   <System.Diagnostics.DebuggerStepThrough()> _
   Private Sub InitializeComponent()
       Me.Label6 = New System.Windows.Forms.Label
       Me.Label5 = New System.Windows.Forms.Label
       Me.Label4 = New System.Windows.Forms.Label
       Me.Label3 = New System.Windows.Forms.Label
       Me.Label2 = New System.Windows.Forms.Label
       Me.Label1 = New System.Windows.Forms.Label
       Me.btnDelete = New System.Windows.Forms.Button
       Me.btnAdd = New System.Windows.Forms.Button
       Me.btnLast = New System.Windows.Forms.Button
       Me.btnNext = New System.Windows.Forms.Button
       Me.btnPrev = New System.Windows.Forms.Button
       Me.btnFirst = New System.Windows.Forms.Button
       Me.txtZip = New System.Windows.Forms.TextBox
       Me.txtState = New System.Windows.Forms.TextBox
       Me.txtCity = New System.Windows.Forms.TextBox
       Me.txtStreet = New System.Windows.Forms.TextBox
       Me.txtLastName = New System.Windows.Forms.TextBox
       Me.txtFirstName = New System.Windows.Forms.TextBox
       Me.SuspendLayout()
       "
       "Label6
       "
       Me.Label6.AutoSize = True
       Me.Label6.Location = New System.Drawing.Point(176, 104)
       Me.Label6.Name = "Label6"
       Me.Label6.Size = New System.Drawing.Size(22, 13)
       Me.Label6.TabIndex = 35
       Me.Label6.Text = "Zip"
       "
       "Label5
       "
       Me.Label5.AutoSize = True
       Me.Label5.Location = New System.Drawing.Point(8, 104)
       Me.Label5.Name = "Label5"
       Me.Label5.Size = New System.Drawing.Size(32, 13)
       Me.Label5.TabIndex = 34
       Me.Label5.Text = "State"
       "
       "Label4
       "
       Me.Label4.AutoSize = True
       Me.Label4.Location = New System.Drawing.Point(8, 80)
       Me.Label4.Name = "Label4"
       Me.Label4.Size = New System.Drawing.Size(24, 13)
       Me.Label4.TabIndex = 33
       Me.Label4.Text = "City"
       "
       "Label3
       "
       Me.Label3.AutoSize = True
       Me.Label3.Location = New System.Drawing.Point(8, 56)
       Me.Label3.Name = "Label3"
       Me.Label3.Size = New System.Drawing.Size(35, 13)
       Me.Label3.TabIndex = 32
       Me.Label3.Text = "Street"
       "
       "Label2
       "
       Me.Label2.AutoSize = True
       Me.Label2.Location = New System.Drawing.Point(8, 32)
       Me.Label2.Name = "Label2"
       Me.Label2.Size = New System.Drawing.Size(58, 13)
       Me.Label2.TabIndex = 31
       Me.Label2.Text = "Last Name"
       "
       "Label1
       "
       Me.Label1.AutoSize = True
       Me.Label1.Location = New System.Drawing.Point(8, 8)
       Me.Label1.Name = "Label1"
       Me.Label1.Size = New System.Drawing.Size(57, 13)
       Me.Label1.TabIndex = 30
       Me.Label1.Text = "First Name"
       "
       "btnDelete
       "
       Me.btnDelete.Location = New System.Drawing.Point(240, 144)
       Me.btnDelete.Name = "btnDelete"
       Me.btnDelete.Size = New System.Drawing.Size(32, 24)
       Me.btnDelete.TabIndex = 29
       Me.btnDelete.Text = "X"
       "
       "btnAdd
       "
       Me.btnAdd.Location = New System.Drawing.Point(200, 144)
       Me.btnAdd.Name = "btnAdd"
       Me.btnAdd.Size = New System.Drawing.Size(32, 24)
       Me.btnAdd.TabIndex = 28
       Me.btnAdd.Text = "+"
       "
       "btnLast
       "
       Me.btnLast.Location = New System.Drawing.Point(104, 144)
       Me.btnLast.Name = "btnLast"
       Me.btnLast.Size = New System.Drawing.Size(32, 24)
       Me.btnLast.TabIndex = 27
       Me.btnLast.Text = ">>"
       "
       "btnNext
       "
       Me.btnNext.Location = New System.Drawing.Point(72, 144)
       Me.btnNext.Name = "btnNext"
       Me.btnNext.Size = New System.Drawing.Size(32, 24)
       Me.btnNext.TabIndex = 26
       Me.btnNext.Text = ">"
       "
       "btnPrev
       "
       Me.btnPrev.Location = New System.Drawing.Point(40, 144)
       Me.btnPrev.Name = "btnPrev"
       Me.btnPrev.Size = New System.Drawing.Size(32, 24)
       Me.btnPrev.TabIndex = 25
       Me.btnPrev.Text = "<"
       "
       "btnFirst
       "
       Me.btnFirst.Location = New System.Drawing.Point(8, 144)
       Me.btnFirst.Name = "btnFirst"
       Me.btnFirst.Size = New System.Drawing.Size(32, 24)
       Me.btnFirst.TabIndex = 24
       Me.btnFirst.Text = "<<"
       "
       "txtZip
       "
       Me.txtZip.Anchor = CType(((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Left) _
                   Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
       Me.txtZip.Location = New System.Drawing.Point(200, 104)
       Me.txtZip.Name = "txtZip"
       Me.txtZip.Size = New System.Drawing.Size(72, 20)
       Me.txtZip.TabIndex = 23
       "
       "txtState
       "
       Me.txtState.Location = New System.Drawing.Point(72, 104)
       Me.txtState.Name = "txtState"
       Me.txtState.Size = New System.Drawing.Size(32, 20)
       Me.txtState.TabIndex = 22
       "
       "txtCity
       "
       Me.txtCity.Anchor = CType(((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Left) _
                   Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
       Me.txtCity.Location = New System.Drawing.Point(72, 80)
       Me.txtCity.Name = "txtCity"
       Me.txtCity.Size = New System.Drawing.Size(200, 20)
       Me.txtCity.TabIndex = 21
       "
       "txtStreet
       "
       Me.txtStreet.Anchor = CType(((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Left) _
                   Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
       Me.txtStreet.Location = New System.Drawing.Point(72, 56)
       Me.txtStreet.Name = "txtStreet"
       Me.txtStreet.Size = New System.Drawing.Size(200, 20)
       Me.txtStreet.TabIndex = 20
       "
       "txtLastName
       "
       Me.txtLastName.Anchor = CType(((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Left) _
                   Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
       Me.txtLastName.Location = New System.Drawing.Point(72, 32)
       Me.txtLastName.Name = "txtLastName"
       Me.txtLastName.Size = New System.Drawing.Size(200, 20)
       Me.txtLastName.TabIndex = 19
       "
       "txtFirstName
       "
       Me.txtFirstName.Anchor = CType(((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Left) _
                   Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
       Me.txtFirstName.Location = New System.Drawing.Point(72, 8)
       Me.txtFirstName.Name = "txtFirstName"
       Me.txtFirstName.Size = New System.Drawing.Size(200, 20)
       Me.txtFirstName.TabIndex = 18
       "
       "Form1
       "
       Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
       Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
       Me.ClientSize = New System.Drawing.Size(278, 175)
       Me.Controls.Add(Me.Label6)
       Me.Controls.Add(Me.Label5)
       Me.Controls.Add(Me.Label4)
       Me.Controls.Add(Me.Label3)
       Me.Controls.Add(Me.Label2)
       Me.Controls.Add(Me.Label1)
       Me.Controls.Add(Me.btnDelete)
       Me.Controls.Add(Me.btnAdd)
       Me.Controls.Add(Me.btnLast)
       Me.Controls.Add(Me.btnNext)
       Me.Controls.Add(Me.btnPrev)
       Me.Controls.Add(Me.btnFirst)
       Me.Controls.Add(Me.txtZip)
       Me.Controls.Add(Me.txtState)
       Me.Controls.Add(Me.txtCity)
       Me.Controls.Add(Me.txtStreet)
       Me.Controls.Add(Me.txtLastName)
       Me.Controls.Add(Me.txtFirstName)
       Me.Name = "Form1"
       Me.Text = "UseCurrencyManager"
       Me.ResumeLayout(False)
       Me.PerformLayout()
   End Sub
   Friend WithEvents Label6 As System.Windows.Forms.Label
   Friend WithEvents Label5 As System.Windows.Forms.Label
   Friend WithEvents Label4 As System.Windows.Forms.Label
   Friend WithEvents Label3 As System.Windows.Forms.Label
   Friend WithEvents Label2 As System.Windows.Forms.Label
   Friend WithEvents Label1 As System.Windows.Forms.Label
   Friend WithEvents btnDelete As System.Windows.Forms.Button
   Friend WithEvents btnAdd As System.Windows.Forms.Button
   Friend WithEvents btnLast As System.Windows.Forms.Button
   Friend WithEvents btnNext As System.Windows.Forms.Button
   Friend WithEvents btnPrev As System.Windows.Forms.Button
   Friend WithEvents btnFirst As System.Windows.Forms.Button
   Friend WithEvents txtZip As System.Windows.Forms.TextBox
   Friend WithEvents txtState As System.Windows.Forms.TextBox
   Friend WithEvents txtCity As System.Windows.Forms.TextBox
   Friend WithEvents txtStreet As System.Windows.Forms.TextBox
   Friend WithEvents txtLastName As System.Windows.Forms.TextBox
   Friend WithEvents txtFirstName As System.Windows.Forms.TextBox

End Class</source>

Data binding

<source lang="vbnet">Public Class Form2

   Inherits System.Windows.Forms.Form
  1. 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.Container
   Private WithEvents textBox1 As System.Windows.Forms.TextBox
   Private WithEvents button1 As System.Windows.Forms.Button
   "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.
   <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
       Me.textBox1 = New System.Windows.Forms.TextBox()
       Me.button1 = New System.Windows.Forms.Button()
       Me.SuspendLayout()
       "
       "textBox1
       "
       Me.textBox1.Location = New System.Drawing.Point(48, 56)
       Me.textBox1.Name = "textBox1"
       Me.textBox1.TabIndex = 0
       Me.textBox1.Text = "textBox1"
       "
       "button1
       "
       Me.button1.Location = New System.Drawing.Point(56, 96)
       Me.button1.Name = "button1"
       Me.button1.TabIndex = 1
       Me.button1.Text = "button1"
       "
       "Form2
       "
       Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
       Me.ClientSize = New System.Drawing.Size(292, 273)
       Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.button1, Me.textBox1})
       Me.Name = "Form2"
       Me.Text = "Form1"
       Me.ResumeLayout(False)
   End Sub
  1. End Region
   Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button1.Click
       Dim sConnection As String = _
       "Provider=SQLOLEDB.1;" & _
       "Password=sqlpassword;" & _
       "Persist Security Info=True;" & _
       "User ID=sa;" & _
       "Initial Catalog=CD;" & _
       "Data Source=(local)"
       Dim sSQL As String
       sSQL = "SELECT ArtistID, ArtistName From Artist"
       Dim objConn _
        As New OleDb.OleDbConnection(sConnection)
       Dim objDataAdapter _
         As New OleDb.OleDbDataAdapter(sSQL, objConn)
       Dim objDS _
         As New DataSet("Artists")
       Dim objDV _
         As DataView
       Try
           objConn.Open()
       Catch myException As System.Exception
           Windows.Forms.MessageBox.Show(myException.Message)
       End Try
       If objConn.State = ConnectionState.Open Then
           Try
               objDataAdapter.Fill(objDS, "Disc")
               objConn.Close()
               Dim objTable As DataTable
               objTable = objDS.Tables("Disc")
               objDV = objTable.DefaultView
               textBox1.DataBindings.Add("Text", objDV, "ArtistName")
           Catch myexception As Exception
               Windows.Forms.MessageBox.Show(myException.Message)
           End Try
       End If
   End Sub

End Class</source>