Contact Form 7 在输入中检索 $_SESSION

Question

I would need to insert within an input value, the value coming from a $ _SESSION, searching on google I found this regarding cookies:

functions:

function sb_cf7_cookie($atts){
    extract(shortcode_atts(array(
        'key' => -1,
    ), $atts));

    if($key == -1) return '';
    $val = '';

    if( isset( $_COOKIE[$key] ) ){
        $val = $_COOKIE[$key];
    }

    return $val;
}
add_shortcode('SB_CF7_COOKIE', 'sb_cf7_cookie');

in cf7:

[dynamichidden field-name "SB_CF7_COOKIE key='COOKIE_NAME'"]

how can make this with $ _SESSION ?

this is my code for $_SESSION

function dd_register_session(){
    if (!session_id()) {
        session_start();
        if($_GET['r']){
            $_SESSION['referrer']=$_GET['r'];
        }
    }
}
add_action('after_setup_theme','dd_register_session', 1);


add_action('wp_logout', 'end_session');
add_action('wp_login', 'end_session');
add_action('end_session_action', 'end_session');

function end_session() {
    session_destroy ();
}

Answer 1

Here's a way to do this by rolling your own form tag. Add this to your theme functions.php

To use this, the form tag name would be the name of the session variable. So, if you're looking for $_SESSION['referrer'] then the form tag name should be referrer

So the form tag in the contact form would be [session_var referrer]

In the email you would put [referrer].

add_action('wpcf7_init', function (){
    wpcf7_add_form_tag( 'session_var' , 'cf7_session_variable_callback', array('name-attr' => true) );
}); 
function cf7_session_variable_callback($tag){
  $tag = new WPCF7_FormTag( $tag );
  $value = (!empty($_SESSION[$tag->name])) ? $_SESSION[$tag->name] : 'not set';
  $output = '<input type="hidden" name="'.$tag->name.'" value="'.$value.'">';
  return $output;
}