How to make server side validations

Question

When user tries to submit form forcefully even after Validation message occurs then another message comes which is 'prevent this page from creating additional dialogs' and a checkbox after selecting checkbox script is disabled .My question is
1. that how to prevent this message
2. Or how to make server side validations which are created using filtertextboxextender .
Shall we use regularexpressvalidator ?
3. Is there any alternative?
Thanks in advance

suresh Shewale · Answer

ya we are putting server side validations but even then browser stops responding .In debug I saw that no source available for AsyncFileUpload.After publish I saw that this Chrome supports very well but Firefox stops responding.So what is solution

Wim Sturkenboom · Answer

[quote] then another message comes which is 'prevent this page from creating additional dialogs' [/quote] I guess you're using Chrome as the browser? If so it's the user's decision to allow those popups (or not). I only use server-side validation (trying to limit javascript to the minimum).

Anubhav Chaudhary · Answer

Your question is now clear