Jquery.validate uses remote to implement AJAX validation paradigm

Jquery.validate is a powerful form verification plug-in, of course, also perfect support for Ajax validation, so that it can be convenient, fast to check the user name, etc. exist.

Html/js Source section:

<form action= "" Name= "Infos" id= "Infos" >

<p> User name: <input type= "text" name= "username" id= "username"/></p>

<p><input type= "Submit" Name= "Sub"/></p>

</form>

<script type= "Text/javascript" >

$ (function () {

$ (' #infos '). Validate ({

Debug:false,

Onkeyup:false,

rules:{

username:{

Required:true,

remote:{

Type: "POST",

URL: "ajax.php",//Request address

data:{

Username:function () {return $ ("#username"). Val ();

}

}

}

},

messages:{

username:{

Required: "User name must be filled in",

Remote: "User name already exists"

}

},

Submithandler:function (form) {

Alert ("Validation passed");

}

});

});

</script>

PHP Source section:

<?php

if ($_request[' username '] = = ' php ')

{

Exit ("false"); User name already exists

}

Else

{

Exit ("true"); User name does not exist, validation passes, output "true", and End program

}

?>

Example Run Effect:

Note that when the server output is true or false, do not output directly, enclose in quotation marks (as shown above)