C＃：从树视图拖放到数据集XML文件

Question

我想从树视图拖放&到datagrid视图。 drag的代码工作正常，但代码drop不起作用。请告诉我在这里做什么错误？

我无法给数据集添加新的值。

private void DataGridView1OnDragDrop(object sender, DragEventArgs e) 
     { 
      Point dscreen = new Point(e.X, e.Y); 
      Point dclient = dataGridView1.PointToClient(dscreen); 
      DataGridView.HitTestInfo hitTest = dataGridView1.HitTest(dclient.X, dclient.Y); 

      if (hitTest.ColumnIndex == 0 && hitTest.Type == DataGridViewHitTestType.Cell) 
      { 
       e.Effect = DragDropEffects.Move; 
       var ds = (DataSet) dataGridView1.DataSource; 
       dataGridView1.Rows.Insert(hitTest.RowIndex, "test", "test", "test", "test"); 

      } 
      else 
      { 
       e.Effect = DragDropEffects.None; 
      } 

     } 

    private void getDataGridFromXml() 
     { 
      try 
      { 
       XmlReader xmlFile; 
       xmlFile = XmlReader.Create(@"C:\Depth.xml", new XmlReaderSettings()); 
       DataSet ds = new DataSet(); 
       ds.ReadXml(xmlFile); 
       dataGridView1.DataSource = ds.Tables[0]; 
      } 
      catch (Exception ex) 
      { 
       MessageBox.Show(ex.ToString()); 
      } 
     } 

XML：

<Product> 

<Apple> 
<Type>Best</Type> 
<Trace>Spain</Trace> 
<Quantity>1000</Quantity> 
<Description>Notihng</Description> 
</Apple> 

</Product> 

Answer 1

最后，这里是解决方案。只需要从drag函数定义treenode并将参数指定到datagridview中即可。

private void treeView1_ItemDrag(object sender, ItemDragEventArgs e) 
      { 
       // Move the dragged node when the left mouse button is used. 
       var node = e.Item as TreeNode; 

       if(node.Parent == null) 
        return; 

       var root = FindTraceRootNode(node); 
       var i = new string[] { root.Nodes[0].Nodes[0].Text, 
        root.Nodes[1].Nodes[0].Text, 
        root.Nodes[2].Nodes[0].Text, 
        root.Nodes[3].Nodes[0].Text }; 

       if (e.Button == MouseButtons.Left) 
       { 
        DoDragDrop(i, DragDropEffects.Move); 
       } 

       // Copy the dragged node when the right mouse button is used. 
       else if (e.Button == MouseButtons.Right) 
       { 
        DoDragDrop(i, DragDropEffects.Copy); 
       } 
      } 

      private TreeNode FindTraceRootNode(TreeNode node) 
      { 
       while (node.Parent != treeView1.Nodes[0]) 
       { 
        node = node.Parent; 
       } 
       return node; 
      } 

      // Set the target drop effect to the effect 
      // specified in the ItemDrag event handler. 
      private void treeView1_DragEnter(object sender, DragEventArgs e) 
      { 
       e.Effect = e.AllowedEffect; 
      } 

      // Select the node under the mouse pointer to indicate the 
      // expected drop location. 
      private void TreeView1OnDragOver(object sender, DragEventArgs e) 
      { 
       // Retrieve the client coordinates of the mouse position. 
       Point targetPoint = treeView1.PointToClient(new Point(e.X, e.Y)); 

       // Select the node at the mouse position. 
       treeView1.SelectedNode = treeView1.GetNodeAt(targetPoint); 
      } 


      private void DataGridView1OnDragOver(object sender, DragEventArgs e) 
      { 
       e.Effect = DragDropEffects.Move; 
      } 

      private void DataGridView1OnDragDrop(object sender, DragEventArgs e) 
      { 
       Point dscreen = new Point(e.X, e.Y); 
       Point dclient = dataGridView1.PointToClient(dscreen); 
       DataGridView.HitTestInfo hitTest = dataGridView1.HitTest(dclient.X, dclient.Y); 

       if (hitTest.ColumnIndex == 0 && hitTest.Type == DataGridViewHitTestType.Cell) 
       { 
        e.Effect = DragDropEffects.Move; 
        //dataGridView1.Rows.Insert(hitTest.RowIndex, "hitTest", "hitTest", "hitTest", "hitTest"); 
        var data = (object[]) e.Data.GetData(typeof(string[])); 
        dataGridView1.Rows.Insert(hitTest.RowIndex, data); 
       } 
       else 
       { 
        e.Effect = DragDropEffects.None; 
       } 

      }