您只是错过了 $ return 和 $ product ...下面的函数可以与内置的钩子一起使用。

You were just missing the $return and $product from your function...The below function will work otherwise with the built in hook.

function wc_remove_quantity_field_from_cart( $return, $product ) {

if ( is_cart() ) return true;

}

add_filter( 'woocommerce_is_sold_individually', 'wc_remove_quantity_field_from_cart', 10, 2 );