public void GetVCodeFromFile()
{
Random r = new Random();
if (string.IsNullOrEmpty(vcodeFile ))
{
vcodeFile = "captcha\\shanghailigong";
}
var pics= Directory.GetFiles(vcodeFile,"*.*",SearchOption.TopDirectoryOnly).Where(f=>f.EndsWith(".jpg")||f.EndsWith (".png")).ToList ();
string url = pics[r.Next (0,pics.Count )];
imgurl = url;
Image img = Image.FromFile(url);
pictureBox1.Image = img;
pborigin.Load(url);
}
/// <summary>