C#winfrom实现窗口贴边隐藏 类似QQ的面板

界面上拖一个Timer控件

using System;
using System.Drawing;
using System.Windows.Forms;

namespace winfrom
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            this.TopMost = true;

            this.timer1.Start();
        }

        private void timer1_Tick(object sender, EventArgs e)
        {
            if (this.Bounds.Contains(Cursor.Position))
            {
                switch (this.StopAanhor)
                {
                    case AnchorStyles.Top:
                        this.Location = new Point(this.Location.X, 0);
                        break;
                    case AnchorStyles.Left:
                        this.Location = new Point(0, this.Location.Y);
                        break;
                    case AnchorStyles.Right:
                        this.Location = new Point(Screen.PrimaryScreen.Bounds.Width - this.Width, this.Location.Y);
                        break;
                    case AnchorStyles.Bottom:
                        this.Location = new Point(this.Location.X, Screen.PrimaryScreen.Bounds.Height - this.Height);
                        break;
                }
            }
            else
            {
                switch (this.StopAanhor)
                {
                    case AnchorStyles.Top:
                        this.Location = new Point(this.Location.X, (this.Height - 4) * (-1));
                        break;
                    case AnchorStyles.Left:
                        this.Location = new Point((-1) * (this.Width - 4), this.Location.Y);
                        break;
                    case AnchorStyles.Right:
                        this.Location = new Point(Screen.PrimaryScreen.Bounds.Width - 4, this.Location.Y);
                        break;
                    case AnchorStyles.Bottom:
                        this.Location = new Point(this.Location.X, (Screen.PrimaryScreen.Bounds.Height - 4));
                        break;
                }
            }
        }
        internal AnchorStyles StopAanhor = AnchorStyles.None;
        private void mStopAnhor()
        {
            if (this.Top <= 0 && this.Left <= 0)
            {
                StopAanhor = AnchorStyles.None;
            }
            else if (this.Top <= 0)
            {
                StopAanhor = AnchorStyles.Top;
            }
            //else if (this.Left <= 0)
            //{
            // StopAanhor = AnchorStyles.Left;
            //}
            else if (this.Left >= Screen.PrimaryScreen.Bounds.Width - this.Width)
            {
                StopAanhor = AnchorStyles.Right;
            }
            else if (this.Top >= Screen.PrimaryScreen.Bounds.Height - this.Height)
            {
                StopAanhor = AnchorStyles.Bottom;
            }
            else
            {
                StopAanhor = AnchorStyles.None;
            }
        }
        private void Form1_LocationChanged(object sender, EventArgs e)
        {
            this.mStopAnhor();
        }
    }
}