C# 窗体吸附

Question

RT：
类似于 QQ的 吸附功能 
就是把窗体 拖到右上角 快到的时候 自动吸附到 右上角 ，
鼠标在拖动窗体的时候又改回来··咋搞·····

Answer 1

做一个判断
if (this.Left < xxx) this.Left = 0;

Answer 2

为你的窗体设置属性，例如public Point 吸附之前窗体的最后坐标;然后再你的执行“吸附”功能的代码的第一行采集窗体左上角坐标和设置这个属性，“改回来”这个部分使用它。“吸附”，就是在触发拖动事件（鼠标移动事件，同时当前鼠标一直按下没有抬起来）并且没有设置这个属性（这个属性为null）时检测一下左边、右边、下边、上边。而“改回来”，就是这个事件中当这个属性不为null时的状态。

Answer 3

放一个timer1控件，interval设置成1秒//实现接近屏幕窗体边源吸附
        private void timer1_Tick(object sender, EventArgs e)
        {
            
            if (this.WindowState != System.Windows.Forms.FormWindowState.Minimized)
            {
                if (Cursor.Position.X > this.Left && Cursor.Position.X < this.Right && Cursor.Position.Y > this.Top && Cursor.Position.Y < this.Bottom)
                {
                    if (this.Top < 0)
                    {
                        this.Top = -5;
                        this.Show();
                    }
                    else if (this.Left < 0)
                    {
                        this.Left = -5;
                        this.Show();
                    }
                    else if (this.Left + this.Width >= Screen.PrimaryScreen.WorkingArea.Width)
                    {
                        this.Left = Screen.PrimaryScreen.WorkingArea.Width - this.Width + 5;
                        this.Show();
                    }
                }
                else
                {
                    if (this.Top <= 4)
                    {
                        this.Top = 5 - this.Height;
                        if (this.Left <= 4)
                        {
                            this.Left = -5;
                        }
                        else if (this.Left + this.Width >= Screen.PrimaryScreen.WorkingArea.Width - 4)
                        {
                            this.Left = Screen.PrimaryScreen.WorkingArea.Width - this.Width + 5;
                        }
                    }
                    else if (this.Left <= 4)
                    {
                        this.Left = 5 - this.Width;
                    }
                    else if (this.Left + this.Width >= Screen.PrimaryScreen.WorkingArea.Width - 4)
                    {
                        this.Left = Screen.PrimaryScreen.WorkingArea.Width - 5;
                    }
                }
            }        }