try
            {
                using (OpenFileDialog openfile = new OpenFileDialog())
                {
                    openfile.Filter = "jpg jpeg图像文件|*.jpg;*.jpeg|Png图像文件(*.png)" + "| *.png |所有文件(*.*)|*.*";
                    if (openfile.ShowDialog() == DialogResult.OK && (openFileDialog1.FileName != ""))
                    {
                        using (FileStream fs = new FileStream(openfile.FileName, FileMode.Open, FileAccess.Read))
                        {
                        image = Image.FromStream(fs);  
                        myPanel.BackgroundImage = image;
                        myPanel.BackgroundImageLayout = ImageLayout.Stretch; 
                        }
                           
                    }
                }
                GC.Collect();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }






winform 打开文件管理 选择图片作为 panel的背景

winform打开文件对话框（图片类型）
实现功能：
①菜单的打开菜单项点击后弹出对话框。
②使用过滤器功能过滤出相应格式的图片，选择一个图片，点击打开后把所选图片显示到窗体上。
③窗体中拖拽控件：MenuStrip（菜单栏）、OpenFileDialog（文件对话框）、PictureBox（图片框），Name属性之如下：

代码如下：
//菜单中文件下的“打开”项的click事件

private void tsmOpen_Click(object sender, EventArgs e)

{

//当弹出选择对话框时，判断是否单击了“打开”键

DialogResult dr = openFileDialog1.ShowDialog();

if (dr == DialogResult.OK)

//PictureBox加载图片

pictureBox1.Load(openFileDialog1.FileName);

//pictureBox1.Image = Image.FromFile(openFileDialog1.FileName);

}

//页面的Load事件

private void _3_3_Load(object sender, EventArgs e)

{

//PictureBox所加载的图片刚好填充满

pictureBox1.SizeMode = PictureBoxSizeMode.StretchImage;

//可打开文件分类

openFileDialog1.Filter = “png图片|.png|jpg、jpeg图片|.jpg;.jpeg|全部|.*”;
    }

如有转载请注明来源： www.dreamload.cn/blog/?p=337&preview=true  （洋葱先生）

Winform的PictureBox中的图片实现类似ppt的棋盘的动画效果：


程序下载：点击打开链接
http://download.csdn.net/detail/softimite_zifeng/9732779

1. 将图片等比例缩放，然后在绑定到PictureBox的Image中。注：必须要先将图片等比例缩放，不能只是简单地把PictureBox的SizeMode属性设置为Zoom。
等比例缩放函数：点击打开链接
2. 使用线程播放动画。
//播放动画线程
private void playThread()
{
    try
    {
        if (logoPb.Image != null)
        {
            try
            {
                Bitmap sBitmap = (Bitmap)logoPb.Image;
                //图片分块显示
                logoPb.Image = null;
                Graphics g = logoPb.CreateGraphics();
                int blockWidth = logoPb.Width / 6;
                int blockHeight = logoPb.Height / 6;
                //划分块
                Rectangle[] Blocks = new Rectangle[39];
                for (int i = 0; i < 3; i++)
                {
                    for (int j = 0; j < 6; j++)
                    {
                        Blocks[13 * i + j] = new Rectangle(blockWidth * j, 2 * blockHeight * i, blockWidth, blockHeight);
                    }
                    for (int j = 0; j < 5; j++)
                    {
                        Blocks[13 * i + j + 7] = new Rectangle(blockWidth * j + blockWidth / 2, 2 * blockHeight * i + blockHeight, blockWidth, blockHeight);
                    }
                    Blocks[13 * i + 6] = new Rectangle(0, 2 * blockHeight * i + blockHeight, blockWidth / 2, blockHeight);
                    Blocks[13 * i + 12] = new Rectangle(5 * blockWidth + blockWidth / 2, 2 * blockHeight * i + blockHeight, blockWidth / 2, blockHeight);
                }
                //将图片按上面的块分割
                Bitmap[] BitmapBlocks = new Bitmap[39];
                for (int i = 0; i < 39; i++)
                {
                    BitmapBlocks[i] = sBitmap.Clone(Blocks[i], System.Drawing.Imaging.PixelFormat.DontCare);
                }
                //以块形式显示动画
                for (int x = 1; x <= blockWidth; x++)
                {
                    for (int i = 0; i < 39; i++)
                    {
                        if (i == 6 || i == 12 || i == 19 || i == 25 || i == 32 || i == 38)
                        {
                            if (x > blockWidth / 2)
                            {
                                Bitmap bitmap = BitmapBlocks[i].Clone(new Rectangle(0, 0, x - blockWidth / 2, blockHeight), System.Drawing.Imaging.PixelFormat.DontCare);
                                g.DrawImage(bitmap, Blocks[i].X, Blocks[i].Y);
                            }
                        }
                        else
                        {
                            Bitmap bitmap = BitmapBlocks[i].Clone(new Rectangle(0, 0, x, blockHeight), System.Drawing.Imaging.PixelFormat.DontCare);
                            g.DrawImage(bitmap, Blocks[i].X, Blocks[i].Y);
                        }
                    }
                    //Thread.Sleep(1);
                }
                g.Flush();
                g.Dispose();
                sBitmap.Dispose();
            }
            catch { }
            finally
            {
                //防止动画出错，恢复为原始图片
                //logoPb.Size = new Size(744, 498); 
                logoPb.Image = null;
                logoPb.Image = ZoomImage(new Bitmap(@".\Image\logo.jpg"), logoPb.Height, logoPb.Width);
                //允许再次播放动画
                allowplay = true;
            }
        }
        else
        {
            allowplay = true;
        }
    }
    catch { }
}
3. 创建线程，播放动画。
private void playAnimation()
{
    //播放动画
    if (allowplay)
    {
        //动画播放期间禁止再次播放
        allowplay = false;
        Thread playthr = new Thread(playThread);
        playthr.IsBackground = true;
        playthr.Start();
    }
}

一般用到的是doc和docx
还有图片类型，模式是一样的：
fileDialog.Filter = "所有文档(*.doc;*.docx)|*.doc;*.docx|所有文件(*.*)|*.*";