<?php $row = get_row_index(); ?>
<tr data-rownum="'. $row .'">
  <td>
    <span class="deletecontrat iconfont_d" data-toggle="tooltip" data-placement="right" title="Effacer ?">r</span>
  </td>
</tr>

jQuery( document ).on( 'click', '.deletecontrat', function() {

    $rownumjs = $(this).parent().parent().data("rownum");

    jQuery.post(
            ajaxurl,
            {
                'action': 'mon_action',
                'param': $rownumjs
            }
            ,
            function(response){
                    console.log(response);
            }
    );

});

function add_js_scripts() {
    wp_enqueue_script( 'script', get_template_directory_uri().'/custom/js/ajax.js', array('jquery'), '1.0', true );
    wp_localize_script('script', 'ajaxurl', admin_url( 'admin-ajax.php' ) );
}
add_action('wp_enqueue_scripts', 'add_js_scripts');




function mon_action() {

    $param = $_POST['param'];

    delete_row("field_5c8fa4201b65f", 1, $post_id);

    echo $param;
    die();
}
add_action( 'wp_ajax_mon_action', 'mon_action' );
add_action( 'wp_ajax_nopriv_mon_action', 'mon_action' );