Validating filenames with regularexpressionvalidator
You can assign any name to a validation group, but you must use the same name for all members of the group.
Everything works great, the upload is fine, but the error message posts Jessica Cao Sincerely, Microsoft Online Community Support “Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question.So in your problem, there must be one of the Validator Controls in the Validation Group is not Valid after postback.It is obvious the Regular Expression Validtor caused the problem.Traditionally, Web developers have faced a tough choice when adding form validation logic to their pages.
You can add form validation routines to your server-side code, or you can add the validation routines to your client-side code.
You should be warned, however, that client-side validation works only with Microsoft Internet Explorer version 4.0 and higher. If you request a page that contains a validation control, and you are using Microsoft Internet Explorer version 4.0 or higher, Java Script code is automatically sent to your browser.