Question

我在基于C＃.net的Windows应用程序中工作...在应用程序中我动态创建控件并将鼠标事件添加到那个..但是在移动子控件时它移出了父控件..我在Code下面试过..但是它没有用......那我们怎么做呢？

private Point start = Point.Empty;
private bool _mapPackageIsMoving;    
Control SelectedControl = null;

 private void button3_Click_1(object sender, EventArgs e)
{
    Label lbl = new Label();
    lbl.Name = "id1";
    lbl.Text = "move";


    lbl.MouseDown += new MouseEventHandler(label1_MouseDown);
    lbl.MouseMove += new MouseEventHandler(label1_MouseMove);
    lbl.MouseUp += new MouseEventHandler(label1_MouseUp);


    this.panel2.Controls.Add(lbl);

    SelectedControl = lbl;
}

void label1_MouseUp(object sender, MouseEventArgs e)
{
    _mapPackageIsMoving = false;
}

void label1_MouseMove(object sender, MouseEventArgs e)
{
    Label lControl = sender as Label;
    if (lControl != null)
    {
        if (_mapPackageIsMoving)
        {
        int nx = Math.Min(Math.Max(lControl.Left + (e.X - start.X), 0), lControl.Parent.Width - SelectedControl.Width);
        int ny = Math.Min(Math.Max(lControl.Top + (e.Y - start.Y), 0), lControl.Parent.Height - SelectedControl.Height);

            lControl.Location = new Point(nx, ny);
        }
    }
}

void label1_MouseDown(object sender, MouseEventArgs e)
{
    start = e.Location;
    _mapPackageIsMoving = true;
}

Answer 1

您需要剪切光标，即阻止光标移动到父母标签的面板之外。以下更改应该有所帮助。

void label1_MouseDown(object sender, MouseEventArgs e)
{
    start = e.Location;
    _mapPackageIsMoving = true;
    Cursor.Clip = panel2.RectangleToScreen(panel2.ClientRectangle);
}

void label1_MouseUp(object sender, MouseEventArgs e)
{
    _mapPackageIsMoving = false;
    Cursor.Clip = null;
}

CodeProject上的

Drag and Drop on a Windows Form是一个方便的参考（代码在VB.NET中）。

如何防止子控件移出父控件在使用C＃.net的鼠标移动事件中？

1 个答案: