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如何剪切、复制和粘贴扩展树节点?

treenode copy-paste c#-4.0 treeview visual-studio-2010

User2400 · 技术社区 · 15 年前

我有一个使用.NET框架4.0版的C_项目,它运行在Vs2010上。我已经创建了一个树视图,其中填充了一些扩展的树节点。我希望用户能够通过上下文菜单或键盘快捷键(而不仅仅是拖放)将这些节点复制、剪切和粘贴到剪贴板。

复制时代码运行良好,但当我尝试粘贴这些节点时,会引发此错误: 无法将“system.io.memoryStream”类型的对象强制转换为“namespace path.treenodeex”类型。

这是我的剪切/复制/粘贴方法。

public void Copy()
{
    Clipboard.SetData("Tree Node Ex", CurrentTreeNode.Clone());
}


public void Paste()
{
    CurrentTreeNode.Nodes.Add((TreeNodeEx)Clipboard.GetData("Tree Node Ex"));
}

我怀疑问题与序列化有关,但我尝试实现ISerizable接口和[serializable]属性,但没有任何效果。

有什么建议吗?

4 回复 | 直到 15 年前

User2400 15 年前

结果发现,在每个扩展树节点上,我都有一个存储额外信息的字典。显然,您不能序列化字典,所以这会阻止任何树节点被序列化。

我实施 ISerializable 对于这些扩展树节点,然后将字典转换为两个列表,然后在反序列化构造函数中将其转换回字典。

leppie 15 年前

试试这个:

Clipboard.GetDataObject().GetData(typeof(TreeNodeEx))

Sandeep Puvvadi 11 年前

public void copy()
{
tempNode = TreeView.SelectedNode;
}
public void paste()
{
TreeView.SelectedNode.Nodes.Add(new TreeNode(tempNode.Text));
            tNode = TreeView.SelectedNode.LastNode;
            for (int i = 0; i <= tempNode.Nodes.Count - 1; i++)
            {
                TreeNode NodeClone = (TreeNode)tempNode.Nodes[i].Clone();
                tNode.Nodes.Add(NodeClone);
            }
public void cut()
{
tempNode = TreeView.SelectedNode;
            TreeView.SelectedNode.Remove();
}

Martin 11 年前

老东西,但我花了几个小时来面对同样的问题,所以这里是什么工作:

Imports System.Runtime.Serialization

Public Class Form1

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
    Me.TV.Nodes.Clear()
    Dim tNode As New TemplateNode()
    Me.TV.Nodes.Add(tNode)
    For i As Integer = 1 To 5
        Dim newNode As New TemplateNode()
        tNode.Nodes.Add(newNode)
        tNode = newNode
    Next
    Me.TV.ExpandAll()
End Sub


Private Sub TV_ItemDrag(sender As Object, e As ItemDragEventArgs) Handles TV.ItemDrag
    DoDragDrop(Me.TV.SelectedNode, DragDropEffects.Copy + DragDropEffects.Move + DragDropEffects.Scroll)
End Sub
Private Sub TV_DragEnter(sender As Object, e As DragEventArgs) Handles TV.DragEnter
    e.Effect = DragDropEffects.Move
End Sub
Private Sub TV_DragOver(sender As Object, e As DragEventArgs) Handles TV.DragOver
    e.Effect = DragDropEffects.Move
    If (e.KeyState And 8) = 8 Then
        e.Effect += DragDropEffects.Copy
    End If
End Sub
Private Sub TV_DragDrop(sender As Object, e As DragEventArgs) Handles TV.DragDrop
    Dim TemplateNode As TemplateNode = e.Data.GetData(GetType(TemplateNode))
    Me.TV.Nodes.Add(TemplateNode.Clone())
End Sub


Private Sub bCopy_Click(sender As Object, e As EventArgs) Handles bCopy.Click
    My.Computer.Clipboard.SetData("TemplateNode", Me.TV.SelectedNode)
End Sub
Private Sub bCut_Click(sender As Object, e As EventArgs) Handles bCut.Click
    My.Computer.Clipboard.SetData("TemplateNode", Me.TV.SelectedNode)
    Me.TV.SelectedNode.Remove()
End Sub
Private Sub bPaste_Click(sender As Object, e As EventArgs) Handles bPaste.Click
    Dim TemplateNode As TemplateNode = My.Computer.Clipboard.GetData("TemplateNode")
    If Me.TV.SelectedNode Is Nothing Then
        Me.TV.Nodes.Add(TemplateNode)
    Else
        Me.TV.SelectedNode.Nodes.Add(TemplateNode)
    End If
End Sub

End Class


<Serializable()> _
Public Class TemplateNode
    Inherits TreeNode

Public MyString As String = "MyStringValue"
Public MyDateTime As DateTime = DateTime.Now
Public MyBytes() As Byte

Public Sub New()
    Dim buff(255) As Byte
    For i As Integer = 0 To buff.GetUpperBound(0)
        buff(i) = CByte(Rnd() * 100)
    Next
    Me.MyBytes = buff
    Me.Text = Guid.NewGuid().ToString()
End Sub
Protected Friend Sub New(info As SerializationInfo, context As StreamingContext)
    MyBase.New(info, context)
End Sub

End Class