It is not a plugin, it is just a simple file call on ajax.

我的Js代码

$(\'.pkg-btn\').click(function(){
    var this_id = $(this).parent().attr(\'id\');
    var url = templateUrl+\'/tw-add-to-cart-ajax.php\';
    $.ajax({
        type: \'POST\',
        url: url,
        data: ({selected_package_id: this_id}),
        dataType: \'json\',
        success: function(data1) {
            console.log(data1);
            $(\'#conditions\').show();
        }
    });
});

我的php文件代码

<?php

//        $product_id = $_POST[\'selected_package_id\'];
//        echo $product_id; // It displays id - works fine here
//        exit();

    add_action(\'woocommerce_add_to_cart\', \'custome_add_to_cart\');

    function custome_add_to_cart() {

         echo \'hook called\'; // This is not showing any message
         exit();

        global $woocommerce;
        $product_id = $_POST[\'selected_package_id\'];

        echo $product_id; // This is not displaying id
        exit();

        $found = false;
        //check if product already in cart
        if ( sizeof( WC()->cart->get_cart() ) > 0 ) {
            foreach ( WC()->cart->get_cart() as $cart_item_key => $values ) {
                $_product = $values[\'data\'];
                if ( $_product->id == $product_id )
                    $found = true;
            }
            // if product not found, add it
            if ( ! $found ){
                WC()->cart->add_to_cart( $product_id );
            }
        } else {
            // if no products in cart, add it
            WC()->cart->add_to_cart( $product_id );
        }
    }

在调用hook之前，我在php文件中获得传递的id并对其进行回显。它显示id，意味着js将数据传递给php，php也会获得该id，但当我调用hook时，它显示错误：jquery-3.4.1.min.js:2 POST domain-url/wp-content/themes/my-theme-folder/tw-add-to-cart-ajax.php 500 (Internal Server Error) 并在网络中显示消息This request has no response data available

<?php

echo \'hook called\'; // This is not showing any message
    exit();

global $woocommerce;
$product_id = $_POST[\'selected_package_id\'];

echo $product_id; // This is not displaying id
exit();

$found = false;
//check if product already in cart
if ( sizeof( WC()->cart->get_cart() ) > 0 ) {
    foreach ( WC()->cart->get_cart() as $cart_item_key => $values ) {
        $_product = $values[\'data\'];
        if ( $_product->id == $product_id )
            $found = true;
    }
    // if product not found, add it
    if ( ! $found ){
        WC()->cart->add_to_cart( $product_id );
    }
} else {
    // if no products in cart, add it
    WC()->cart->add_to_cart( $product_id );
}