void UploadBtn_Click(Object sender, EventArgs e)
    {
      
     String UploadedFile = MyFile.PostedFile.FileName;
     int ExtractPos =  UploadedFile.LastIndexOf("\\") + 1;
   
     //to retrieve only Filename from the complete path
     String UploadedFileName =  UploadedFile.Substring(ExtractPos,UploadedFile.Length - ExtractPos);
       
     
     // Display information about posted file. Div is invisible by default    
     FileName.InnerHtml =UploadedFileName;
       MyContentType.InnerHtml = MyFile.PostedFile.ContentType;
       ContentLength.InnerHtml = MyFile.PostedFile.ContentLength.ToString();

       FileDetails.Visible = true; //div is made visible
       // Save uploaded file to server at the in the Pics folder
     
       String percorso= Request.PhysicalPath;
       int daEliminare= percorso.Length -29;
       string nuovo = percorso.Substring(0, daEliminare) + "foto/";

    
       String idUser= Request.Form["idUser"];
     
     const string FMT = "yyyy-MM-dd";
    DateTime now1 = DateTime.Now;
    string DataTxt = now1.ToString(FMT);
    DataTxt=DataTxt.Replace("-","");

       MyFile.PostedFile.SaveAs(nuovo +  idUser+ DataTxt+ UploadedFileName);

    //thumbnail creation starts
    try
    {
    //Read in the image filename whose thumbnail has to be created
     String imageUrl=  UploadedFileName;



    
    //You may even specify a standard thumbnail size
    int imageWidth  = 245; 
    int imageHeight = 184;
   

        imageUrl = nuovo + imageUrl;
        System.Drawing.Image fullSizeImg = System.Drawing.Image.FromFile(imageUrl);
        int altezzaNuova;
        int larghezzaNuova;

        larghezzaNuova = fullSizeImg.Width * imageHeight / fullSizeImg.Height;
 

    System.Drawing.Image.GetThumbnailImageAbort dummyCallBack = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);

        System.Drawing.Image thumbNailImg = fullSizeImg.GetThumbnailImage(larghezzaNuova, imageHeight, dummyCallBack, IntPtr.Zero);
      
    
    
        string nuovoFileName;
        string[] words = UploadedFileName.Split('.');
       
       String MyString = "min_" +  idUser+ DataTxt  +words[0] + ".jpg";


        thumbNailImg.Save(nuovo + MyString, ImageFormat.Jpeg);
     thumbNailImg.Dispose();

   
     
   
        
   }

   catch(Exception ex)
   {
    Response.Write("An error occurred - " + ex.ToString());
   }

}