我挂上了数量选择器来更改设计，效果很好。但问题是我不能设置max value 动态。如果库存中只有2件物品，我需要设置max-value 同于2。目前情况并非如此。

下面是我正在使用的钩子，

function woocommerce_quantity_input($data = null) {

global $product;
if (!$data) {
  $defaults = array(
    \'input_name\'   => \'quantity\',
    \'input_value\'   => \'1\',
    \'max_value\'     => apply_filters( \'cw_woocommerce_quantity_input_max\', \'\', $product ),
    \'min_value\'     => apply_filters( \'woocommerce_quantity_input_min\', \'\', $product ),
    \'step\'         => apply_filters( \'woocommerce_quantity_input_step\', \'1\', $product ),
    \'style\'         => apply_filters( \'woocommerce_quantity_style\', \'float:left;\', $product )
  );
}else {
  $defaults = array(
    \'input_name\'   => $data[\'input_name\'],
    \'input_value\'   => $data[\'input_value\'],
    \'step\'         => apply_filters( \'cw_woocommerce_quantity_input_step\', \'1\', $product ),
    \'max_value\'     => apply_filters( \'cw_woocommerce_quantity_input_max\', \'\', $product ),
    \'min_value\'     => apply_filters( \'cw_woocommerce_quantity_input_min\', \'\', $product ),
    \'style\'         => apply_filters( \'cw_woocommerce_quantity_style\', \'float:left;\', $product )
  );
}

if ( ! empty( $defaults[\'min_value\'] ) )
  $min = $defaults[\'min_value\'];
else 
  $min = 1;


if ( ! empty( $defaults[\'max_value\'] ) )
   $max = $defaults[\'max_value\'];
else 
   $max = 15;


if ( ! empty( $defaults[\'input_value\'] ) )
   $defval = $defaults[\'input_value\'];
else 
   $defval = 1; 


if ( ! empty( $defaults[\'step\'] ) )
   $step = $defaults[\'step\'];
else 
   $step = 1

?>
<div class="woo-single-selection">
  <p>Quantity <?php //echo $product->get_stock_quantity(); ?></p>
  <div>
    <span class="woo-qty-num woo-quantity-input-number-decrement">-</span> 
    <input class="woo-quantity-input-number input-text qty text cw_qty" type="number" step="<?php echo $step ?>" value="<?php echo $defval ?>" min="<?php echo $min ?>" max="<?php echo $max ?>" name="<?php echo esc_attr( $defaults[\'input_name\'] ) ?>" title="<?php echo _x( \'Qty\', \'Product Description\', \'woocommerce\' ) ?>"  pattern="[0-9]*" inputmode="numeric"><span class="woo-qty-num woo-quantity-input-number-increment">+</span>
  </div>
</div>
<?php
}