Is there a simples way to do this?
I have 2 TextBox, for email input, with regex and compare validator. If user input invalid email and a different email at second textbox, is shown two error messages. But i want to display just one error message at a time.
In this case, you might try writing a custom validator to perform the regex first, and only do the comparison validation if the entry passes the regex validation (or the other way around, however you want to do it). There may be a simpler solution, but this is the best way I can think of.
Nice question but couldnt find a solution for this question. But I would not recommend it. Its always better to show all the required fields error message. Think about a form with lot of input fields and I wouldn't know the error until I scroll down and click the submit button.
What are you going to achieve by limiting the number of error messages displayed?
Maybe using ValidationSummary control might help you to solve your problem in a different way. Ok, it won't produce only one error message, but it will place them where you want in your page. Just set the text property of your validation controls to * end place a validationsummary control. Hope this helps.