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I have this in my JavaScript part:

        action : 'my_php_action_to_do',
    function( response ) {
        alert( response.mycode );

and this in my my_php_action_to_do php function:

function my_php_action_to_do() {

    $send_to_response['mycode'] = '1234';
    echo json_encode( $send_to_response );


I can execute the php code in the php function and run the result post javascirpt code, but the problem I am facing is how to send the variable from the php function back to response and alert it or use in whatever way.

Now I am getting undefined in a popup window as a result.

How to do that in WordPress?

share|improve this question
up vote 3 down vote accepted

You need to send the var through your ajax request:

//be suer that this var is pointing to wp-admin/admin-ajax.php
    action              : 'my_php_action_to_do',
    //here your var and its value
    my_var              : 'the_value'
function( response ) {
    response = jQuery.parseJSON(response);

In your my_php_action_to_do function:

function my_php_action_to_do(){
    $var['message'] = $_POST['my_var'];
    //Send back the $var value in json format. You can send it in other format if you want
    echo json_encode( $var );

//Don't forget to add your my_php_action_to_do function to wp_ajax_* action hook.

add_action('wp_ajax_my_php_action_to_do', 'my_php_action_to_do');
//or this if you want it to work in the frontend
add_action('wp_ajax_nopriv_my_php_action_to_do', 'my_php_action_to_do');
share|improve this answer
This part I know ;) – Derfder Sep 6 '13 at 15:29
But I want to get the value of php variable back after the script in the function is done and send it back to javascript, so I can alert it in the response. how to do taht? – Derfder Sep 6 '13 at 15:30
Hmm, I tried it and I get in alert undefined. Shoulc I use echo before json_encode? – Derfder Sep 6 '13 at 15:43
No. Can you edit your question and post the full code you are trying? – cybmeta Sep 6 '13 at 15:50
function( response ) { alert( response.mycode ); } in JS and in PHP I have this: $send_to_response['mycode'] = '1234'; echo json_encode( $send_to_response ); and I am gettign undefined in the popup ;( – Derfder Sep 6 '13 at 15:55

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