Now I also noticed if I used <html> formatting in the ContentText, it will not display "..." for text exceeding the display window size, it would just not be displayed.
For example, this is the formatting I put for ContentText
"<html>Item for "
"Item Code: "
"Item Name: "
", has been deleted successfully. "
Which I will pass to a private function ShowDesktopAlert(string, string);
rdaRawMaterial.CaptionText = strCaption;
rdaRawMaterial.ContentText = strContent;
"Unable to display Desktop Alert."
"No Desktop Alert"
But it's displayed incompletely. It would only displayed up to the first <br>.