DataGridComboBox

网上也有很多类似文章，我是总结他们的，再加以革新绝对原创的。网上关于VB.NET的代码实在是太少了。虽然C#和VB.net大部分代码都通用稍作修改即可。

废话不说了贴代码

DataGridComboBox.Designer.vb   

Partial Class DataGridComboBox
    Inherits System.Windows.Forms.ComboBox
    _
    Public Sub New(ByVal container As System.ComponentModel.IContainer)
        MyClass.New()


        'Windows.Forms 类撰写设计器支持所必需的
        If (container IsNot Nothing) Then
            container.Add(Me)
        End If


    End Sub

    'Component 重写 Dispose，以清理组件列表。
    _
    Protected Overrides Sub Dispose(ByVal disposing As Boolean)
        Try
            If disposing AndAlso components IsNot Nothing Then
                components.Dispose()
            End If
        Finally
            MyBase.Dispose(disposing)
        End Try
    End Sub


    '组件设计器所必需的
    Private components As System.ComponentModel.IContainer


    '注意: 以下过程是组件设计器所必需的
    '可使用组件设计器修改它。
    '不要使用代码编辑器修改它。
    _
    Private Sub InitializeComponent()
        Me.components = New System.ComponentModel.Container()
        Me.ContextMenuStrip1 = New System.Windows.Forms.ContextMenuStrip(Me.components)
        Me.编辑ToolStripMenuItem = New System.Windows.Forms.ToolStripMenuItem()
        Me.ContextMenuStrip1.SuspendLayout()
        Me.SuspendLayout()
        '
        'ContextMenuStrip1
        '
        Me.ContextMenuStrip1.Items.AddRange(New System.Windows.Forms.ToolStripItem() {Me.编辑ToolStripMenuItem})
        Me.ContextMenuStrip1.Name = "ContextMenuStrip1"
        Me.ContextMenuStrip1.Size = New System.Drawing.Size(196, 26)
        '
        '编辑ToolStripMenuItem
        '
        Me.编辑ToolStripMenuItem.Name = "编辑ToolStripMenuItem"
        Me.编辑ToolStripMenuItem.Size = New System.Drawing.Size(195, 22)
        Me.编辑ToolStripMenuItem.Text = "ToolStripMenuItem1"
        Me.ContextMenuStrip1.ResumeLayout(False)
        Me.ResumeLayout(False)


    End Sub
    Friend WithEvents ContextMenuStrip1 As System.Windows.Forms.ContextMenuStrip
    Friend WithEvents 编辑ToolStripMenuItem As System.Windows.Forms.ToolStripMenuItem


End Class

学vb.net的应该知道以上代码应该放在哪里(VS2010)

DataGridComboBox.vb 以下为程序区

Public Class DataGridComboBox
#Region "Class Data"
    Private Const WM_LBUTTONDOWN As UInt32 = &H201
    Private Const WM_LBUTTONDBLCLK As UInt32 = &H203
    Private Const WM_KEYF4 As UInt32 = &H134
    Private Const WM_CTLCOLORLISTBOX As UInt32 = &H134
    Private WithEvents Grid As MyDataGrid
    Private tsDD As ToolStripDropDown
    Dim GridViewHost As ToolStripControlHost
#End Region


    Public Sub New()
        MyBase.New()


        '组件设计器需要此调用。
        InitializeComponent()
        tsDD = New ToolStripDropDown()
        Grid = New MyDataGrid
        Grid.Width = 0
        Grid.Height = 0
        Grid.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.ColumnHeader
        GridViewHost = New ToolStripControlHost(Grid)
        tsDD.AutoSize = True
        GridViewHost.AutoSize = False
        Me.ContextMenuStrip = ContextMenuStrip1
    End Sub
    Dim mSourceTable As DataTable
    Overloads Property DataSource As DataTable
        Get
            Return mSourceTable
            'Return Grid.SourceTable
        End Get
        Set(ByVal value As DataTable)
            mSourceTable = value
            Grid.Columns.Clear()
            If mSourceTable Is Nothing Then Return
            Dim ColLent As Integer
            For Each Col As DataColumn In mSourceTable.Columns
                Grid.Columns.Add(Col.ColumnName, Col.ColumnName)
                Grid.Columns(Col.ColumnName).DataPropertyName = Col.ColumnName
                ColLent += Grid.Columns(Col.ColumnName).Width
            Next


            For Each Row As DataRow In mSourceTable.Rows
                Dim GridRow As DataGridViewRow
                Dim n As Integer = Grid.Rows.Add()
                GridRow = Grid.Rows(n)
                For Each Col As DataGridViewColumn In Grid.Columns
                    GridRow.Cells(Col.Name).Value = Row(Col.Name)
                Next
            Next
            GridViewHost.Width = ColLent + Grid.RowHeadersWidth
            GridViewHost.Height = CInt((Me.Font.Height + 3) * 8)
        End Set
    End Property
#Region "Methods"
    Private Function CalculatePoz() As Point
        Dim point As New Point(0, Me.Height)
        If (Me.PointToScreen(New Point(0, 0)).Y + Me.Height + Me.Grid.Height) > Screen.PrimaryScreen.WorkingArea.Height Then
            point.Y = -Me.Grid.Height - 7
        End If


        Return point
    End Function
#End Region
    Protected Overrides Sub WndProc(ByRef m As Message)
        '#Region "WM_KEYF4"
        If m.Msg = WM_KEYF4 Then
            Me.Focus()
            Me.tsDD.Refresh()
            If Not Me.tsDD.Visible Then
                If mSourceTable Is Nothing Then Return
                tsDD.Items.Add(GridViewHost)
                tsDD.Show(Me, Me.CalculatePoz())
            End If
            Return
        End If
        '#End Region


        '#Region "WM_LBUTTONDBLCLK"
        If m.Msg = WM_LBUTTONDBLCLK OrElse m.Msg = WM_LBUTTONDOWN Then
            If Not Me.tsDD.Visible Then
                If mSourceTable Is Nothing Then Return
                tsDD.Items.Add(GridViewHost)
                tsDD.Show(Me, Me.CalculatePoz())
            End If
            Return
        End If
        '#End Region


        MyBase.WndProc(m)
    End Sub


    Private Sub Grid_CellMouseEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles Grid.CellMouseEnter
        If e.RowIndex < 0 Or e.ColumnIndex < 0 Then Return
       'BindingControlToToolTip(Grid, Grid.Rows(e.RowIndex).Cells(e.ColumnIndex).Value)’这个是绑定气泡提示的代码，可以不用的。
    End Sub
    Private Sub Grid_DoubleClick(ByVal sender As DataGridView, ByVal e As System.EventArgs) Handles Grid.DoubleClick
        Dim Row As DataGridViewRow = sender.CurrentRow
        Me.Text = ""
        If Row IsNot Nothing Then
            For Each Cell As DataGridViewCell In Row.Cells
                If Me.Text.Trim.Length = 0 Then
                    Me.Text = Cell.Value.ToString
                Else
                    Me.Text = Me.Text & "->" & Cell.Value.ToString
                End If
            Next
            BindingControlToToolTip(Me, Me.Text)
        End If
        Me.tsDD.Close()
    End Sub

‘这里是我的编辑区，可以按照自己的需求修改这里
    Private Sub 编辑ToolStripMenuItem_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles 编辑ToolStripMenuItem.Click
        Dim Frm As New Frm表格项目设定(mSourceTable)
        Frm.ShowDialog()
    End Sub
  
End Class

这里就算完成了，放到自己的程序 可以直接使用此控件.

有这个可举一反三了，可以把ComboBox跟更多的控件组合起来使用，这个程序里其实我也有纳闷的地方，比如直接DataGridView控件直接赋予DataSource一个DataTable显示出来的时候什么也没有，最后我不得不自己把数据取出来放到DataGridView控件里去，而不是采用数据绑定的方式。如果哪位仁兄能解决这个疑惑希望可以告知与我，谢谢。希望此段代码对新手有些帮助。网上很多代码不尽如人意。也有类似控件但是有缺陷。不能在窗体之外显示，受到TopLevelControl的限制。这里弹出的位置只和屏幕有关，所以就方便许多了。

这里包含了其他控件http://download.csdn.net/detail/earnmoney08/6935749（TreeView和ComboBox的组合以及加强版的TreeView）