Winform窗体控件图片过多后卡顿问题

近期做抽奖软件，作出后发现加载图片和不加载图片，程序刷新的很慢，且卡顿的很严重；严重影响用户体验；

经过网络大量资料查询，尝试了一下方法：

方法一：预加载图片方法

在窗体加载后，将图片读进来，然后释放资源；代码如下：

            string path = System.Environment.CurrentDirectory + "\\backgroundImage.jpg";
            Bitmap bm = new Bitmap(path);
            Bitmap newBm = new Bitmap(bm);

            bm.Dispose();
            this.panel1.BackgroundImage = newBm;
            this.panel1.BackgroundImageLayout = ImageLayout.Stretch;
            this.BackgroundImage = newBm;

方法二：图片加载采用容器panel

不设置窗体的背景图片，在窗体上放置panel，然后设置panel的背景图片

结果：无效

方法三：窗体启用双缓存

winform窗体属性直接设置即可，已可以通过以下代码设置

SetStyle(ControlStyles.UserPaint, true);
SetStyle(ControlStyles.AllPaintingInWmPaint, true); // 禁止擦除背景.
SetStyle(ControlStyles.DoubleBuffer, true); // 双缓冲

protected override CreateParams CreateParams
{
    get
    {
        CreateParams paras = base.CreateParams;
        paras.ExStyle |= 0x02000000;
        return paras;
    }
}

结果：效果没有改善

方法五：重新封装panel类

public class PanelEx : Panel
{
    /// <summary>
    /// OnPaintBackground 事件
    /// </summary>
    /// <param name="e"></param>
    protected override void OnPaintBackground(PaintEventArgs e)
    {
        // 重载基类的背景擦除函数，
        // 解决窗口刷新，放大，图像闪烁
        return;
    }

    /// <summary>
    /// OnPaint 事件
    /// </summary>
    /// <param name="e"></param>
    protected override void OnPaint(PaintEventArgs e)
    {
        // 使用双缓冲
        this.DoubleBuffered = true;
        // 背景重绘移动到此
        if (this.BackgroundImage != null)
        {
            e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            e.Graphics.DrawImage(
                this.BackgroundImage,
                new System.Drawing.Rectangle(0, 0, this.Width, this.Height),
                0,
                0,                this.BackgroundImage.Width,                this.BackgroundImage.Height,                System.Drawing.GraphicsUnit.Pixel);
        }
        base.OnPaint(e);
    }
}

 this.panel1 = new LuckDrawForm.PanelEx();

  this.panel1.BackColor = System.Drawing.Color.Transparent;
            this.panel1.BackgroundImageLayout = System.Windows.Forms.ImageLayout.Stretch;
this.panel1.Dock = System.Windows.Forms.DockStyle.Fill;
            this.panel1.Location = new System.Drawing.Point(0, 0);

private PanelEx panel1;

http://www.cnblogs.com/candyzhmm/p/5961394.html