jQuery Validator Plugin - check for existing Username/Email in mysql database

Question

I\'ve successfully created a form that submits and adds users to a mysql database, and form validation with \'jQuery Validator\' plugin works great for everything except che

Answer 1

js code

username: {
        required: true,
        minlength: 5,
        remote: '/userExists'
       },

Php code to check if exist and return messages

public function userExists()
{
    $user = User::all()->lists('username');
    if (in_array(Input::get('username'), $user)) {
        return Response::json(Input::get('username').' is already taken');
    } else {
        return Response::json(Input::get('username').' Username is available');
    }
}

Answer 2

For WordPress & PHP

Most important thing is instead or return true or false, need to echo 'true' or 'false'

jQuery or JS

   email: {
     required: true,
     minlength: 6,
     email: true,
     remote:{
        url : 'your ajax url',
        data: { 
                'action': 'is_user_exist',
              },
        },
   },

WordPress or PHP Backend Code

In backend you will automatically get the value of field via GET method.

/*
 *@ Check user exists or not
 */
if( !function_exists('is_user_exists_ajax_function') ):
    function is_user_exists_ajax_function() {
        $email = $_GET['email'];
        if( empty($email) && is_email($email) ):
            wp_send_json_error( new \WP_Error( 'Bad Request' ) );
        endif;

        $is_email = email_exists( $email );

        if($is_email):
            echo 'false';
        else:
            echo 'true';
        endif;

        wp_die();
    }
    add_action( 'wp_ajax_is_user_exist', 'is_user_exists_ajax_function' ); 
    add_action( 'wp_ajax_nopriv_is_user_exist', 'is_user_exists_ajax_function' ); 
endif;

Answer 3

$.validator.addMethod("checkExists", function(value, element)
{
    var inputElem = $('#register-form :input[name="email"]'),
        data = { "emails" : inputElem.val() },
        eReport = ''; //error report

    $.ajax(
    {
        type: "POST",
        url: validateEmail.php,
        dataType: "json",
        data: data, 
        success: function(returnData)
        {
            if (returnData!== 'true')
            {
              return '<p>This email address is already registered.</p>';
            }
            else
            {
               return true;
            }
        },
        error: function(xhr, textStatus, errorThrown)
        {
            alert('ajax loading error... ... '+url + query);
            return false;
        }
    });

}, '');

OR

You can use the remote method instead which allows you to do remote checks: http://docs.jquery.com/Plugins/Validation/Methods/remote

Eg.

    $("#yourFormId").validate({
            rules: {
                email: {
                    required: true,
                    email: true,
                    remote: {
                        url: "checkUnameEmail.php",
                        type: "post"
                     }
                }
            },
            messages: {
                email: {
                    required: "Please Enter Email!",
                    email: "This is not a valid email!",
                    remote: "Email already in use!"
                }
            }
        });

checkUnameEmail.php //Eg.

    <?php
    $registeredEmail = array('jenson1@jenson.in', 'jenson2@jenson.in', 'jenson3@jenson.in', 'jenson4@jenson.in', 'jenson5@jenson.in');

    $requestedEmail  = $_REQUEST['email'];

    if( in_array($requestedEmail, $registeredEmail) ){
        echo 'false';
    }
    else{
        echo 'true';
    }
    ?>