我怎么能拖放在对方的DataGridView行？ [英] How could I Drag and Drop DataGridView Rows under each other?

问题描述

我有的DataGridView ，它们界定了名单，其中，MyClass的＆GT; 和我的<$ C $排序C>优先级属性 MyClass的。 所以，我想拖一的DataGridViewRow 到一定的位置，以改变它的优先级属性。

I've DataGridView that bound a List<myClass> and i sort it by "Priority" property in "myClass". So I want to drag an "DataGridViewRow" to certain position to change it's "Priority" property.

我怎么能拖＆放，放下？DataGridView的行 而如何处理？

推荐答案

我发现这个<一href="http://social.msdn.microsoft.com/Forums/en-US/winforms/thread/16b0a44e-35a0-4bc8-9ccd-ec2c62c95a55"相对=nofollow> MSDN上的code样品

请注意以下内容：

1）。 DataGridView的属性AllowDrop必须设置为true（默认为false）。

1). DataGridView property AllowDrop must be set to true (default is false).

2）。下面的例子开箱的时候，DataGridView的是不会数据绑定。否则，将引发InvalidOperationException。如果是数据绑定，你应该处理项目的顺序在数据源。

2). The example below works out of the box when the DataGridView is NOT data-bound. Otherwise it will throw an InvalidOperationException. If it is databound, you should manipulate the order of items in the DataSource.

private Rectangle dragBoxFromMouseDown;
private int rowIndexFromMouseDown;
private int rowIndexOfItemUnderMouseToDrop;
private void dataGridView1_MouseMove(object sender, MouseEventArgs e)
{
    if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
    {
        // If the mouse moves outside the rectangle, start the drag.
        if (dragBoxFromMouseDown != Rectangle.Empty &&
            !dragBoxFromMouseDown.Contains(e.X, e.Y))
        {

            // Proceed with the drag and drop, passing in the list item.                    
            DragDropEffects dropEffect = dataGridView1.DoDragDrop(
            dataGridView1.Rows[rowIndexFromMouseDown],
            DragDropEffects.Move);
        }
    }
}

private void dataGridView1_MouseDown(object sender, MouseEventArgs e)
{
    // Get the index of the item the mouse is below.
    rowIndexFromMouseDown = dataGridView1.HitTest(e.X, e.Y).RowIndex;
if (rowIndexFromMouseDown != -1)
    {
        // Remember the point where the mouse down occurred. 
     // The DragSize indicates the size that the mouse can move 
     // before a drag event should be started.                
        Size dragSize = SystemInformation.DragSize;

        // Create a rectangle using the DragSize, with the mouse position being
        // at the center of the rectangle.
        dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2),
                                                       e.Y - (dragSize.Height / 2)),
                            dragSize);
    }
    else
        // Reset the rectangle if the mouse is not over an item in the ListBox.
        dragBoxFromMouseDown = Rectangle.Empty;
}

private void dataGridView1_DragOver(object sender, DragEventArgs e)
{
    e.Effect = DragDropEffects.Move;
}

private void dataGridView1_DragDrop(object sender, DragEventArgs e)
{
    // The mouse locations are relative to the screen, so they must be 
    // converted to client coordinates.
    Point clientPoint = dataGridView1.PointToClient(new Point(e.X, e.Y));

    // Get the row index of the item the mouse is below. 
    rowIndexOfItemUnderMouseToDrop =
        dataGridView1.HitTest(clientPoint.X, clientPoint.Y).RowIndex;

    // If the drag operation was a move then remove and insert the row.
    if (e.Effect== DragDropEffects.Move)
    {
        DataGridViewRow rowToMove = e.Data.GetData(
            typeof(DataGridViewRow)) as DataGridViewRow;
        dataGridView1.Rows.RemoveAt(rowIndexFromMouseDown);
        dataGridView1.Rows.Insert(rowIndexOfItemUnderMouseToDrop, rowToMove);

    }
}

这篇关于我怎么能拖放在对方的DataGridView行？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！