C# 仿QQ贴边隐藏(Timer)

private void timer1_Tick(object sender, EventArgs e)
{
    timer1.Interval = 200;
    AutoSideHideOrShow();
}
void AutoSideHideOrShow()
{
    int sideThickness = 2;//边缘的厚度，窗体停靠在边缘隐藏后留出来的可见部分的厚度
    //如果窗体最小化或最大化了则什么也不做
    if (this.WindowState == FormWindowState.Minimized || this.WindowState == FormWindowState.Maximized)
    {
        return;
    }
    //如果鼠标在窗体内
    if (Cursor.Position.X >= this.Left && Cursor.Position.X < this.Right && Cursor.Position.Y >= this.Top && Cursor.Position.Y < this.Bottom)
    {
        //如果窗体离屏幕边缘很近，则自动停靠在该边缘
        if (this.Top <= sideThickness)
        {
            this.Top = 0;
        }
        if (this.Left <= sideThickness)
        {
            this.Left = 0;
        }
        if (this.Left >= Screen.PrimaryScreen.WorkingArea.Width - this.Width - sideThickness)
        {
            this.Left = Screen.PrimaryScreen.WorkingArea.Width - this.Width;
        }
    }
    //当鼠标离开窗体以后
    else
    {
        //隐藏到屏幕左边缘
        if (this.Left == 0)
        {
            this.Left = sideThickness - this.Width;
        }
        //隐藏到屏幕右边缘
        else if (this.Left == Screen.PrimaryScreen.WorkingArea.Width - this.Width)
        {
            this.Left = Screen.PrimaryScreen.WorkingArea.Width - sideThickness;
        }
        //隐藏到屏幕上边缘
        else if (this.Top == 0 && this.Left > 0 && this.Left < Screen.PrimaryScreen.WorkingArea.Width - this.Width)
        {
            this.Top = sideThickness - this.Height;
        }
    }
}