有条件地将费用添加到购物车

Question

public function calculate_fees( $fees ){
    global $woocommerce;

    $cart_subtotal   = $woocommerce->cart->subtotal;
    $additional_fee = 0; // Additional fee
    $additional_fee_text = __('Assembling fee : ', 'dornaweb');

    if( $_POST['assembly_fee'] === 'flat_assembly_rate' ){
        $additional_fee = intval( dw_option('flat_assembly_rate') ) ?: 0; // flat assembly fee
        $additional_fee_text .= __(' ( assembly, no warranty )', 'dornaweb');
    } elseif( $_POST['assembly_fee'] === 'percentage_assembly_fee' ) {
        $additional_fee = dw_option('percentage_assembly_fee') ? ( ( intval( dw_option('percentage_assembly_fee') ) / 100 ) * $cart_subtotal ) : 0; // percentage assembly fee
        $additional_fee_text .= __(' ( assembly + one year warranty )', 'dornaweb');
    }

    $woocommerce->cart->add_fee( $additional_fee_text, intval( $additional_fee ), 1 );
}

add_action( 'woocommerce_cart_calculate_fees', array( $this, 'calculate_fees' ) );

让我更多地解释一下这个向导（组装您的PC）：我们在本节中有3个步骤,

• 步骤1：用户从现有产品中选择主板、Ram、Cpu等。
• 步骤2：查看列表并可以更改某些产品的数量（如Ram）
• 步骤3：用户在页面底部看到带有一些选项的最终列表，这些选项可以
  选择装配费用（1.不装配，只购买列表2.装配有一年保修3.装配有无保修），当他们点击“提交”时，所有选择的产品都被添加到购物车，这是我们需要添加该费用的地方，所以只有当客户使用该进度时才应该添加该费用。

我也尝试添加费用，当我添加产品到购物车，但它不工作的方式，当我到购物车页面，没有额外的费用，以这种方式

    /* User chooses list of products ( mainboard, ram, ... ) and can  choose quantity of each product 
and also can choose whether he/she wants to get an assembled computer
or just wants to buy the products individually,
then when he/she hits submit products get added to cart all together
in this step assembling fee should be added and calculated in cart total */
if( !empty( $_POST['action'] ) && $_POST['action'] == 'add' ){
      /**
       * Add each product to cart based on user choice
       */
      foreach( $_POST['products'] as $product_id => $data ) {
            WC()->cart->add_to_cart( $product_id, $data['qty'] );
      }

      /**
       * Add additional fees
       */
      WC()->cart->add_fee( 'Assembling fee', 10 ); // 10 is an example , the fee differs depending on user choice ( no assemble:0, assemlby+warranty:5% of the cart subtotal, assembly+no warranty: a flat fee eg. 20$ )
      WC()->cart->calculate_fees();

      /**
       * Redirect to cart
       */
      wp_safe_redirect( WC()->cart->get_cart_url() );
}

Answer 1

这对我起作用了，以防有人有同样的问题：当产品添加到购物车时，我设置了一些会话，当购物车得到付款或清空时，我取消设置这些会话。

if( !empty( $_POST['action'] ) && $_POST['action'] == 'add' ){
   /**
    * Add each product to cart based on user choice
    */
   foreach( $_POST['products'] as $product_id => $data ) {
        WC()->cart->add_to_cart( $product_id, $data['qty'] );
   }

   /**
    * We set sessions after products added to cart
   */
   WC()->session->set( 'MY_SESSION', 'My_value' );

   /**
    * Redirect to cart
    */
   wp_safe_redirect( WC()->cart->get_cart_url() );
}

现在，当客户被重定向到另一个页面（在本例中是购物车页面）时，我们可以根据该会话确定他/她的购物车的附加费用

function dw_calculate_fees( $cart_object ){
    global $woocommerce;
    if ( is_admin() && ! defined( 'DOING_AJAX' ) ) return;
    if( ! WC()->session->MY_SESSION ) return;

    $cart_subtotal   = $woocommerce->cart->subtotal;
    $additional_fee = null;

    if( WC()->session->MY_SESSION === 'example_a' ){
        $additional_fee = 1;
    } elseif( WC()->session->MY_SESSION === 'example_b' ) {
        $additional_fee = 2;
    } else{
        $additional_fee = 0;
    }

    if( ! is_null( $additional_fee ) ) {
        $woocommerce->cart->add_fee( 'Additional fee ', intval( $additional_fee ), 1 );
    }
}
add_action( 'woocommerce_cart_calculate_fees', 'dw_calculate_fees' );

并且我们需要在购物车被支付或清空时取消设置这些会话：

add_action( 'woocommerce_cart_emptied', 'dw_unset_fee_session' );
function dw_unset_fee_session(){
    unset( WC()->session->MY_SESSION );
}