使用vb.net的拖放操作使用图像

我目前正在尝试简化我们在工作中使用的工具。为此，我想使用拖放方法。这个工具基本上就像用三种不同的积木建造一座塔。在顶部有三个不同块的图像，下面是一个流程布局面板。目标是按所需顺序将块拖动到“流布局”面板中

这是一张代表起始位置的快速图像。（我只是想澄清一下。）

这对我来说是个棘手的部分。我只使用拖放方法将值从一个文本框拖放到另一个文本框中。现在我需要复制图像对象并将其添加到flow布局面板中

这是我用来拖放值的方法

Private MouseIsDown As Boolean = False

Private Sub TextBox1_MouseDown(ByVal sender As Object, ByVal e As _
System.Windows.Forms.MouseEventArgs) Handles TextBox1.MouseDown
    ' Set a flag to show that the mouse is down.
    MouseIsDown = True
End Sub

Private Sub TextBox1_MouseMove(ByVal sender As Object, ByVal e As _
System.Windows.Forms.MouseEventArgs) Handles TextBox1.MouseMove
    If MouseIsDown Then
        ' Initiate dragging.
        TextBox1.DoDragDrop(TextBox1.Text, DragDropEffects.Copy)
    End If
    MouseIsDown = False
End Sub

Private Sub TextBox2_DragEnter(ByVal sender As Object, ByVal e As _
System.Windows.Forms.DragEventArgs) Handles TextBox2.DragEnter
    ' Check the format of the data being dropped.
    If (e.Data.GetDataPresent(DataFormats.Text)) Then
        ' Display the copy cursor.
        e.Effect = DragDropEffects.Copy
    Else
        ' Display the no-drop cursor.
        e.Effect = DragDropEffects.None
    End If
End Sub

Private Sub TextBox2_DragDrop(ByVal sender As Object, ByVal e As _
System.Windows.Forms.DragEventArgs) Handles TextBox2.DragDrop
    ' Paste the text.
    TextBox2.Text = e.Data.GetData(DataFormats.Text)
End Sub

现在，对于下一步，我应该对图像执行相同的操作，以下是我的尝试：

Public Class Form2

    Private MouseIsDown As Boolean = False

    Private Sub PictureBox1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) _
        Handles PictureBox1.MouseDown
        ' Set a flag to show that the mouse is down.
        MouseIsDown = True
    End Sub

    Private Sub PictureBox1_MouseMove(ByVal sender As Object, ByVal e As _
                                   System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseMove
        If MouseIsDown Then
            ' Initiate dragging.
            PictureBox1.DoDragDrop(PictureBox1, DragDropEffects.Copy)
        End If
        MouseIsDown = False
    End Sub

    Private Sub FlowLayoutPanel1_DragEnter(ByVal sender As Object, ByVal e As _
                                           System.Windows.Forms.DragEventArgs) Handles FlowLayoutPanel1.DragEnter
        ' Check the format of the data being dropped.
        If (e.Data.GetDataPresent(DataFormats.Text)) Then
            ' Display the copy cursor.
            e.Effect = DragDropEffects.Copy
        Else
            ' Display the no-drop cursor.
            e.Effect = DragDropEffects.None
        End If
    End Sub

    Private Sub FlowLayoutPanel1_DragDrop(ByVal sender As Object, ByVal e As _
System.Windows.Forms.DragEventArgs) Handles FlowLayoutPanel1.DragDrop
        ' Paste the text.
        FlowLayoutPanel1.Text = e.Data.GetData(DataFormats.Bitmap)
    End Sub

End Class

但如果我这样做，并将picturebox1项拖到面板上，我只会得到不能放下的符号。。这就是我被困的地方。有人能给我提供一些信息如何做到这一点吗？或者给我一些指点

    ' Check the format of the data being dropped.
    If (e.Data.GetDataPresent(DataFormats.Text)) Then

这是不对的。现在拖动的是PictureBox对象，它不是文本，因此该If表达式始终为False。只有在看到PictureBox对象被拖动时，您才会感到高兴。像这样：

    If (e.Data.GetDataPresent(GetType(PictureBox))) Then

与DragDrop事件处理程序中的问题相同，它需要类似：

    Dim pb = CType(e.Data.GetData(GetType(PictureBox)))
    FlowLayoutPanel1.Controls.Add(pb)

---

或者创建一个新的，并指定Image属性，将pb.Image设置为Nothing。要做到这一点，有多种方法，您需要考虑如何让用户纠正错误。

您的

DoDragDrop

以

控件作为拖放数据（与问题标题匹配）启动，但您需要在dragenter中测试
数据格式.Text
。