rerturning response of an ajax post

Question

i am trying to check if an email exists in the db but the function doesn't return a value.

This is the code:

function checkemail(email)
{
    var returnVal = "";
    if (email.indexOf("@") != -1 && email.indexOf(".") != -1)
    {
        $.post( "registreren.php?email=" + email, function( response ) {
            if(response == 1) { returnVal = 1; }
            if(response == 2) { returnVal = 2; }
        });
    }
    else
    {
        returnVal = 3;
    }//email

    return returnVal;

}

EDIT: email is send as a string

Answer 1

Can you use something simple like below

$.ajax({
        url: 'registreren.php',
        type: 'post',
        dataType: "json",
        data: {'email': email},
        success: function (response) {
            if (response == 1)
            {
               returnVal = 1; 
            }
            else
            {
               returnVal = 3; 
            }
        }
    });

instead of

$.post( "registreren.php?email=" + email, function( response ) {
            if(response == 1) { returnVal = 1; }
            if(response == 2) { returnVal = 2; }
    });

Answer 2

I short, You can not return values from ajax calls as it is asynchronous by nature, the statement return value executes before

To address such cases, use callback , a function accepted as argument and which is executed when response is been received ( when asynchronous action is completed ).

Try this:

 function checkemail(email, callback) { var returnVal = ""; if (email.indexOf("@") != -1 && email.indexOf(".") != -1) { $.post("registreren.php?email=" + email, function(response) { callback(response); }); } else { callback(3); } } checkemail('abc@xyz.com', function(val) { alert(val); }); checkemail('INVALID_EMAIL', function(val) { alert(val); }); 

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