有很多方法可以将 ComboBox 控件添加到 DataGrid 控件。其中多数方法涉及到使用 DataGrid 的 ColumnStyles 集合。不过，本文将使用一种较为简单的方法，将下拉 ComboBox 控件添加到 DataGrid 的控件集合。

Imports System.Data.SqlClient
Imports System.Windows.Forms
将下面的代码添加到代码窗口的“Windows 窗体设计器生成代码”部分之后：Public MyCombo As New ComboBox()
    Dim con As New SqlConnection("server=myservername;uid=myid;pwd=mypassword;database=northwind")
    Dim daEmp As New SqlDataAdapter("Select * From Employees", con)

    Public ds As New DataSet()
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        AddHandler MyCombo.TextChanged, AddressOf Ctrls_TextChanged
        'Fill ComboBox list.
        MyCombo.Name = "MyCombo"
        MyCombo.Visible = False
        MyCombo.Items.Clear()
        MyCombo.Items.Add("Sales Representative")
        MyCombo.Items.Add("Inside Sales Coordinator")
        MyCombo.Items.Add("Vice President, Sales")
        MyCombo.Items.Add("Sales Manager")
        MyCombo.Items.Add("Flunky")

      
        daEmp.Fill(ds, "Employees")

        'Set the RowHeight of the DataGrid to the height of the ComboBox.
        DataGrid1.PreferredRowHeight = MyCombo.Height
       
        DataGrid1.DataSource = ds

        DataGrid1.DataMember = "Employees"
        'Add ComboBox to the Control collection of the DataGrid.
        DataGrid1.Controls.Add(MyCombo)
    End Sub

    Private Sub DataGrid1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles DataGrid1.Paint
        If DataGrid1.CurrentCell.ColumnNumber = 3 Then
            MyCombo.Width = DataGrid1.GetCurrentCellBounds.Width
        End If
    End Sub

    Private Sub Ctrls_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs)
        If DataGrid1.CurrentCell.ColumnNumber = 3 Then
            MyCombo.Visible = False
            If DataGrid1.Item(DataGrid1.CurrentCell) & "" = "" Then
                SendKeys.Send("*")
            End If
            DataGrid1.Item(DataGrid1.CurrentCell) = MyCombo.Text
        End If
    End Sub

    Private Sub DataGrid1_CurrentCellChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles DataGrid1.CurrentCellChanged
        If DataGrid1.CurrentCell.ColumnNumber = 3 Then
            MyCombo.Visible = False
            MyCombo.Width = 0
            MyCombo.Left = DataGrid1.GetCurrentCellBounds.Left
            MyCombo.Top = DataGrid1.GetCurrentCellBounds.Top
            MyCombo.Text = DataGrid1.Item(DataGrid1.CurrentCell) & ""
            MyCombo.Visible = True
        Else
            MyCombo.Visible = False
            MyCombo.Width = 0
        End If
    End Sub

    Private Sub DataGrid1_Scroll(ByVal sender As Object, ByVal e As System.EventArgs) Handles DataGrid1.Scroll
        MyCombo.Visible = False
        MyCombo.Width = 0
    End Sub

    Private Sub DataGrid1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles DataGrid1.Click
        MyCombo.Visible = False
        MyCombo.Width = 0
    End Sub