无边框窗体

一、无边框窗体

1.创建无边框窗体

将窗体FormBorderStyle属性设为None

2.设置一个关闭按钮功能

（1）添加一个pictureBox，将背景改为关闭图像

（2）设置鼠标移入，移出，点击等事件

        /// <summary>
        /// 鼠标移入
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void pictureBox1_MouseEnter(object sender, EventArgs e)
        {
            pictureBox1.BackgroundImage = Image.FromFile("G:\WinForm\2016-7-4\Buttons\btn_close_highlight.png");
        }
        /// <summary>
        /// 鼠标移出
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void pictureBox1_MouseLeave(object sender, EventArgs e)
        {
            pictureBox1.BackgroundImage = Image.FromFile("G:\WinForm\2016-7-4\Buttons\btn_close_disable.png");
        }
        /// <summary>
        /// 鼠标按下
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
        {
            pictureBox1.BackgroundImage = Image.FromFile("G:\WinForm\2016-7-4\Buttons\btn_close_down.png");
        }
        /// <summary>
        /// 鼠标点击事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void pictureBox1_Click(object sender, EventArgs e)
        {
            if (MessageBox.Show("是否退出？", "退出",MessageBoxButtons.OKCancel,MessageBoxIcon.Information) == DialogResult.OK)
            {
                this.Close();
            }
        }

3.窗体移动

        //无边框移动
        [DllImport("user32.dll")]
        public static extern bool ReleaseCapture();
        [DllImport("user32.dll")]
        public static extern bool SendMessage(IntPtr hwnd, int wMsg, int wParam, int IParam);
        public const int WM_SYSCOMMAND = 0x0112;
        public const int SC_MOVE = 0xF010;
        public const int HTCAPTION = 0x0002;
        [DllImport("user32")]
        private static extern int SendMessage(IntPtr hwnd, int wMsg, int wParam, IntPtr lParam);
        private const int WM_SETREDRAW = 0xB;

        private void Form4_MouseDown(object sender, MouseEventArgs e)
        {
            if (this.WindowState == FormWindowState.Normal)
            {
                ReleaseCapture();
                SendMessage(this.Handle, WM_SYSCOMMAND, SC_MOVE + HTCAPTION, 0);
            }
        }