关于博易上传文件的一个BUG

当上传同名文件的话，就把原有的给覆盖了。。。
代码有问题
修改，\admin\Pages\Add_entry.aspx

   private void Upload(string virtualFolder, FileUpload control, string fileName)
    {
        string folder = Server.MapPath(virtualFolder);
        if (!Directory.Exists(folder))
            Directory.CreateDirectory(folder);
        int c = 0;
        string savapath = folder + fileName;
        while (File.Exists(savapath))
        {
            c++;
            savapath = folder +c+ fileName;
        }
      
            control.PostedFile.SaveAs(savapath);
       
    }