位置:海鸟网 > IT > ASP.NET >

轻松实现控件间托拽操作 40Star(原作)

轻松实现控件间托拽操作    40Star(原作)  
  
    在Vb.net里实现ListBox之间的托拽,首先要使接受托拽数据的控件的AllowDrop属性设为真。再要处理的就是托拽效果,AllowedEffect是设置托拽的源控件的动作效果,而Effect是设置目标控件的动作。这些东东可以在DragEventArgs Members中查到!

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim i As Int32
        For i = 0 To 9
            ListBox1.Items.Add("Item " & i)
        Next
        ListBox2.AllowDrop = True
    End Sub

    Private Sub ListBox1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles ListBox1.MouseDown
        Dim itemIndex As Integer
        itemIndex = ListBox1.IndexFromPoint(e.X, e.Y)
        If itemIndex >= 0 Then
            ListBox1.DoDragDrop(ListBox1.Items(itemIndex), DragDropEffects.Copy)
        End If
    End Sub

    Private Sub ListBox2_DragEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles ListBox2.DragEnter
        If (e.Data.GetDataPresent(DataFormats.Text)) Then
            e.Effect = DragDropEffects.Copy
        Else
            e.Effect = DragDropEffects.None
        End If
    End Sub

    Private Sub ListBox2_DragDrop(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) Handles ListBox2.DragDrop
        Dim sItem As String
        sItem = e.Data.GetData(DataFormats.Text).ToString
        ListBox2.Items.Add(sItem)
        ListBox1.Items.RemoveAt(ListBox1.FindString(sItem))
    End Sub