C# 如何鼠标拖动无边框窗体

设置了无边框表单，则无法使用鼠标拖动任意位置。

通过以下方式实现

private void FrmLogin_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
mouseOff = new Point(-e.X, -e.Y); //得到变量的值
leftFlag = true; //点击左键按下时标注为true;
}
}

private void FrmLogin_MouseUp(object sender, MouseEventArgs e)
{

if (leftFlag)
{
leftFlag = false;//释放鼠标后标注为false;
}
}

private void FrmLogin_MouseMove(object sender, MouseEventArgs e)
{
if (leftFlag)
{
Point mouseSet = Control.MousePosition;
mouseSet.Offset(mouseOff.X, mouseOff.Y); //设置移动后的位置
Location = mouseSet;
}
}