What is the best choice for developing real-time form validation in ASP.NET

Question

I want to do a real-time form validation on an asp.net form in which, when I lose focus on the field, it shows the error or success of the field input data. I
am looking for the best way to do this.
and if I want to do the same by checking data from an SQL database ... what is the best choice for this?

Answer 1

• jQuery Validator

  definitely the best option

Answer 2

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Answer 3

ASP.NET ValidatorCallout Ajax Control Toolkit . , . , , jQuery.