Php – ajax user name verify

Hello all,

Can you please read and help me out-

The matter is that I am laboring a registration form for the registration onto the site.

And I am deploying jquery Ajax library to check usernames without the requirement for pushing the submit button, however as and when they click off the textbox, it will test out a database using php and return it with json_encode engaging ajax.

Kindly let me know how this can be attained.

Thanks for reading my point.