string strpath;

    protected void Page_Load(object sender, EventArgs e)
    {
        strpath = HttpContext.Current.Request.PhysicalApplicationPath + "1.bmp";
    }
    public byte[] getBytes(string filePath)  //图片转成二进制
    {
        System.IO.FileStream fs = new System.IO.FileStream(filePath, System.IO.FileMode.Open);
        byte[] imgData = new byte[fs.Length];
        fs.Read(imgData, 0, (int)fs.Length);
        return imgData;
    }

    private System.Drawing.Image convertByteToImg(byte[] imgData)  //二进制转成图片
    {
        System.IO.MemoryStream ms = new System.IO.MemoryStream(imgData);
        System.Drawing.Image img = System.Drawing.Image.FromStream(ms);
        return img;
    }

    protected void Button1_Click(object sender, EventArgs e)
    {

        //下面两行可将图片直接显示
        //System.Drawing.Image img = convertByteToImg(getBytes(strpath));
        //img.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);

        //下面几行代码将图片显示在IMAGE中
        byte[] photo = getBytes(strpath);
        //图片路径
        string strPath = "2.JPG";
        string strPhotoPath = Server.MapPath(strPath);
        //保存图片文件
        BinaryWriter bw = new BinaryWriter(File.Open(strPhotoPath,FileMode.OpenOrCreate));
        bw.Write(photo);
        bw.Close();
        //显示图片
        this.Image1.ImageUrl = strPath;
    }