在前面看到了很多关于怎样向DataGrid中添加ComboBox控件的方法。使用的方法全部都是在VB6.0中的方法。
我还是要说说在CSND中发贴的朋友。
现在所谓的.NET编程人员，不知道是怎么了呢！只是停留在使用.NET的编程环境中。并没有真正的了解面向对象的.NET编程思想。
我现在就利用继承DataGridColumnStyle完成向DataGrid中添加ComboBox。
希望这样有助于大家了解真正的面向对象编程的思想。不要只是认为利用VB6.0中的某些方法就是.NET高手了。有这种思想的人都是菜鸟 （希望这么说没有得罪太多的朋友：）下面就是实现的代码：我使用的是VB.NET来完成的。
我熟悉C#,但是VB.NET只是大概了解一下。应该比一些人要高一点点吧！：）
见笑了！由于时间关系没有协注释，请见谅！
Public Class DataGridComboColumn
源代码网推荐 Inherits DataGridColumnStyle
Public WithEvents DGCombo As ComboBox = New ComboBox
源代码网推荐 Private isEditing As Boolean
源代码网推荐 Private _strSelectedText As String
Public Sub New()
源代码网推荐 MyBase.New()
源代码网推荐 DGCombo.Visible = False
源代码网推荐 End Sub
Protected Overrides Sub Abort(ByVal rowNum As Integer)
源代码网推荐 isEditing = False
源代码网推荐 RemoveHandler DGCombo.SelectedValueChanged, AddressOf DGCombo_SelectedValueChanged
源代码网推荐 Invalidate()
End Sub
Protected Overrides Function Commit(ByVal dataSource As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer) As Boolean
源代码网推荐 DGCombo.Bounds = Rectangle.Empty
源代码网推荐 AddHandler DGCombo.SelectedValueChanged, AddressOf DGCombo_SelectedValueChanged
源代码网推荐 If isEditing = False Then
源代码网推荐 Return True
源代码网推荐 End If
isEditing = False
源代码网推荐 Try
源代码网推荐 DGCombo.Text = DGCombo.Text
源代码网推荐 Catch ex As Exception
源代码网推荐 DGCombo.Text = String.Empty
源代码网推荐 End Try
Try
源代码网推荐 Dim value As String = _strSelectedText
源代码网推荐 SetColumnValueAtRow(dataSource, rowNum, value)
源代码网推荐 Catch ex As Exception
源代码网推荐 Abort(rowNum)
源代码网推荐 Return False
源代码网推荐 End Try
源代码网推荐 Invalidate()
源代码网推荐 Return True
End Function
Protected Overloads Overrides Sub Edit(ByVal source As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer, ByVal bounds As System.Drawing.Rectangle, ByVal [readOnly] As Boolean, ByVal instantText As String, ByVal cellIsVisible As Boolean)
源代码网推荐 Dim value As String
源代码网推荐 Try
源代码网推荐 value = CType(GetColumnValueAtRow(source, rowNum), String)
源代码网推荐 Catch ex As Exception
源代码网推荐 SetColumnValueAtRow(source, rowNum, DGCombo.Text)
源代码网推荐 End Try
value = CType(GetColumnValueAtRow(source, rowNum), String)
If (cellIsVisible) Then
源代码网推荐 DGCombo.Bounds = New Rectangle(bounds.X, bounds.Y, bounds.Width, bounds.Height)
源代码网推荐 DGCombo.Text = value
源代码网推荐 DGCombo.Visible = True
源代码网推荐 AddHandler DGCombo.SelectedValueChanged, AddressOf DGCombo_SelectedValueChanged
源代码网推荐 Else
源代码网推荐 DGCombo.Text = value
源代码网推荐 DGCombo.Visible = False
源代码网推荐 End If
If DGCombo.Visible = False Then
源代码网推荐 DataGridTableStyle.DataGrid.Invalidate(bounds)
源代码网推荐 End If
源代码网推荐 End Sub
Protected Overrides Function GetMinimumHeight() As Integer
End Function
Protected Overrides Function GetPreferredHeight(ByVal g As System.Drawing.Graphics, ByVal value As Object) As Integer
End Function
Protected Overrides Function GetPreferredSize(ByVal g As System.Drawing.Graphics, ByVal value As Object) As System.Drawing.Size
End Function
Protected Overloads Overrides Sub Paint(ByVal g As System.Drawing.Graphics, ByVal bounds As System.Drawing.Rectangle, ByVal source As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer)
源代码网推荐 Paint(g, bounds, source, rowNum, True)
源代码网推荐 End Sub
Protected Overloads Overrides Sub Paint(ByVal g As System.Drawing.Graphics, ByVal bounds As System.Drawing.Rectangle, ByVal source As System.Windows.Forms.CurrencyManager, ByVal rowNum As Integer, ByVal alignToRight As Boolean)
源代码网推荐 Paint(g, bounds, source, rowNum, Brushes.Red, Brushes.Blue, alignToRight)
源代码网推荐 End Sub
Protected Overloads Overrides Sub Paint(ByVal g As System.Drawing.Graphics, _
源代码网推荐 ByVal bounds As System.Drawing.Rectangle, _
源代码网推荐 ByVal source As System.Windows.Forms.CurrencyManager, _
源代码网推荐 ByVal rowNum As Integer, _
源代码网推荐 ByVal backBrush As System.Drawing.Brush, _
源代码网推荐 ByVal foreBrush As System.Drawing.Brush, _
源代码网推荐 ByVal alignToRight As Boolean)
Dim strDate As String
源代码网推荐 Dim rect As RectangleF
源代码网推荐 Try
源代码网推荐 strDate = DGCombo.Text
源代码网推荐 strDate = CType(GetColumnValueAtRow(source, rowNum), String)
源代码网推荐 Catch ex As Exception
源代码网推荐 SetColumnValueAtRow(source, rowNum, DGCombo.Text)
源代码网推荐 strDate = CType(GetColumnValueAtRow(source, rowNum), String)
源代码网推荐 End Try
rect.X = bounds.X
源代码网推荐 rect.Y = bounds.Y
源代码网推荐 rect.Height = bounds.Height
源代码网推荐 rect.Width = bounds.Width
g.FillRectangle(backBrush, rect)
源代码网推荐 rect.Offset(0, 2)
源代码网推荐 rect.Height -= 2
g.DrawString(strDate, Me.DataGridTableStyle.DataGrid.Font, foreBrush, rect)
End Sub
Protected Overrides Sub SetDataGridInColumn(ByVal value As DataGrid)
源代码网推荐 MyBase.SetDataGridInColumn(value)
源代码网推荐 If Not (DGCombo.Parent Is Nothing) Then
源代码网推荐 DGCombo.Parent.Controls.Remove(DGCombo)
源代码网推荐 End If
源代码网推荐 If Not (value Is Nothing) Then
源代码网推荐 value.Controls.Add(DGCombo)
源代码网推荐 End If
源代码网推荐 End Sub
Private Sub DGCombo_SelectedValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles DGCombo.SelectedValueChanged
源代码网推荐 isEditing = True
源代码网推荐 MyBase.ColumnStartedEditing(DGCombo)
源代码网推荐 _strSelectedText = DGCombo.Text
源代码网推荐 If _strSelectedText Is Nothing Then
源代码网推荐 _strSelectedText = String.Empty
源代码网推荐 End If
源代码网推荐 End Sub
源代码网推荐End Class
源代码网推荐
以下是使用方法！
Private Sub frmDataGrid_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
源代码网推荐 Call TEST()
源代码网推荐 End Sub
Private Sub TEST()
源代码网推荐 Dim DT As New DataTable("TEST")
源代码网推荐 DT.Columns.Add(New DataColumn("ID"))
源代码网推荐 DT.Columns.Add(New DataColumn("COMBO"))
源代码网推荐 Call AddGridStyle()
源代码网推荐 Call ADDDATA(DT)
源代码网推荐 DBGrid.DataSource = DT
End Sub
Private Sub AddGridStyle()
Dim DBGridStyle As DataGridTableStyle
源代码网推荐 Dim IDColumn As DataGridTextBoxColumn
源代码网推荐 Dim DCColumn As DataGridComboColumn
源代码网推荐
DBGridStyle = New DataGridTableStyle
源代码网推荐 DBGridStyle.MappingName = "TEST"
IDColumn = New DataGridTextBoxColumn
源代码网推荐 IDColumn.MappingName = "ID"
源代码网推荐 IDColumn.HeaderText = "ID"
源代码网推荐 IDColumn.Alignment = HorizontalAlignment.Center
源代码网推荐 IDColumn.Width = 50
源代码网推荐 DBGridStyle.GridColumnStyles.Add(IDColumn)
DCColumn = New DataGridComboColumn
源代码网推荐 Dim i As Integer
源代码网推荐 For i = 0 To 25
源代码网推荐 DCColumn.DGCombo.Items.Add((i + 1).ToString("00000"))
源代码网推荐 Next
源代码网推荐 DCColumn.DGCombo.DropDownWidth = 120
源代码网推荐 DCColumn.MappingName = "COMBO"
源代码网推荐 DCColumn.HeaderText = "COMBO"
源代码网推荐 DCColumn.Alignment = HorizontalAlignment.Center
源代码网推荐 DCColumn.Width = 60
源代码网推荐 DBGridStyle.GridColumnStyles.Add(DCColumn)
DBGrid.TableStyles.Add(DBGridStyle)
End Sub
Private Sub ADDDATA(ByRef DT As DataTable)
源代码网推荐 Dim DROW As DataRow
源代码网推荐 Dim intRow As Integer
For intRow = 0 To 9
源代码网推荐 DROW = DT.NewRow()
源代码网推荐 DROW.Item("ID") = Format(intRow + 1, "000")
源代码网推荐 DROW.Item("COMBO") = Format(intRow + 1, "00000")
源代码网推荐 DT.Rows.Add(DROW)
源代码网推荐 Next
DT.AcceptChanges()
End Sub
源代码网推荐
那么随时在DataGrid中所指定为Combo列中单击。Combo就出现了
