Form not repainting itself

Question

How can I make the FileOpenDialog disappear?

private void ofdAttachment_FileOk(object sender, CancelEventArgs e)
{            

    string fullFilename = ofdAttachment.FileName;
    string filename = Path.GetFileName(fullFilename);
    string dirName = Path.GetDirectoryName(fullFilename);


    this.Parent.Refresh();
    this.Refresh();


    var drv = bdsAttachments.AddNew() as DataRowView;


    var fze = new FastZipEvents();
    fze.ProgressInterval = new TimeSpan(0, 0, 0, 0, 250);
    fze.Progress = new ICSharpCode.SharpZipLib.Core.ProgressHandler(
    (object o, ICSharpCode.SharpZipLib.Core.ProgressEventArgs ex) =>
    {                    
        drv["filename"] = "Compressing: " 
            + ex.PercentComplete.ToString() + "%";
        grdAttachments.Refresh();
        this.Refresh(); // this doesn't work either                    
        Application.DoEvents(); // re: Aamir's answer, neither work
        this.Refresh();

    }
    );



    var ba = new FastZip(fze).CreateZipToArray(dirName, false, filename, null);

    drv["filename"] = filename;
    drv["file_zip_image"] = ba;

    grdAttachments.Refresh();

}

[EDIT: Solved]

using the fire-and-forget approach:

private void ofdAttachment_FileOk(object sender, CancelEventArgs e)
{            
    System.Threading.ThreadPool.QueueUserWorkItem((o) => Attach());
}

void Attach()
{

    if (this.InvokeRequired)
    {
     this.Invoke(new Action(Attach));    
    }
    else
    {

     this.Parent.Refresh();
     this.Refresh();

     string fullFilename = ofdAttachment.FileName;
     string filename = Path.GetFileName(fullFilename);
     string dirName = Path.GetDirectoryName(fullFilename);



     var drv = bdsAttachments.AddNew() as DataRowView;


     var fze = new FastZipEvents();
     fze.ProgressInterval = new TimeSpan(0, 0, 0, 0, 250);
     fze.Progress = new ICSharpCode.SharpZipLib.Core.ProgressHandler(
      (object o, ICSharpCode.SharpZipLib.Core.ProgressEventArgs ex) =>
      {
      drv["filename"] = "Compressing: " 
         + ex.PercentComplete.ToString() + "%";
      grdAttachments.Refresh();                        
      }
     );



     var ba = new FastZip(fze).CreateZipToArray(dirName, false, 
                    filename, null);

     drv["filename"] = filename;
     drv["file_zip_image"] = ba;

     grdAttachments.Refresh();
    }

}

Answer 1

It looks like your file compression is a long running process which prevents the form from repainting until the compression has finished. If you use a BackgroundWorker object and do the compression routine on a background thread, the UI thread will be available for the form to use for painting.

BackgroundWorker info: http://msdn.microsoft.com/en-us/library/8xs8549b.aspx

Answer 2

You can call Application.DoEvents() to achieve this.