If the client message corresponding to the web page is configured to perform runtime error checking, then ePortal-generated code in the code-behind file performs validation when the page is submitted. Refer to Runtime Error Checking for Message Fields and Programming in the Code-Behind File.

If the message field validation detects errors, a popup alert box displays with one or more error messages. In this case, the web page is not submitted. The web page user must dismiss the alert box and correct the errors before continuing. Refer to AlertBox in ePortal Developer Controls for Web Forms Projects.