我更新了。 回答,包括贵方的“数量单位”遴选人(显示选定领域,节省选定价值并在单一产品页上显示)

修订后的法典:

add_action(  woocommerce_product_options_pricing ,  wc_qty_add_product_field  );
function wc_qty_add_product_field() {
    global $product_object;

    $values   = $product_object->get_meta( _qty_args );

    echo  </div><div class="options_group qty-unit hide_if_grouped"> ;

    woocommerce_wp_select( array(
         id                 =>  qty_unit ,
         label              => __(  Product unit ,  woocommerce-quantity-step  ),
         class              =>  qty_unit ,
         options  => array(
             set     =>  Sold as a set ,
             piece   =>  Sold per piece ,
        ),
         desc_tip           =>  true ,
         description        => __(  Choose if the product is sold per piece or as a set. ,  woocommerce  ),
    ) );

    echo  </div><div class="options_group quantity hide_if_grouped">
    <style>div.qty-args.hidden { display:none; }</style> ;

    woocommerce_wp_checkbox( array( // Checkbox.
         id             =>  qty_args ,
         label          => __(  Quantity settings ,  woocommerce  ),
         value          => empty($values) ?  no  :  yes ,
         description    => __(  Enable this to show and enable the additional quantity setting fields. ,  woocommerce  ),
    ) );

    echo  <div class="qty-args hidden"> ;

    woocommerce_wp_text_input( array(
         id                 =>  qty_min ,
         type               =>  number ,
         label              => __(  Minimum Quantity ,  woocommerce-max-quantity  ),
         placeholder        =>   ,
         desc_tip           =>  true ,
         description        => __(  Set a minimum allowed quantity limit (a number greater than 0). ,  woocommerce  ),
         custom_attributes  => array(  step   =>  any ,  min    =>  0 ),
         value              => isset($values[ qty_min ]) && $values[ qty_min ] > 0 ? (int) $values[ qty_min ] : 0,
    ) );

    woocommerce_wp_text_input( array(
         id                 =>  qty_max ,
         type               =>  number ,
         label              => __(  Maximum Quantity ,  woocommerce-max-quantity  ),
         placeholder        =>   ,
         desc_tip           =>  true ,
         description        => __(  Set the maximum allowed quantity limit (a number greater than 0). Value "-1" is unlimited ,  woocommerce  ),
         custom_attributes  => array(  step   =>  any ,  min    =>  -1 ),
         value              => isset($values[ qty_max ]) && $values[ qty_max ] > 0 ? (int) $values[ qty_max ] : -1,
    ) );

    woocommerce_wp_text_input( array(
         id                 =>  qty_step ,
         type               =>  number ,
         label              => __(  Quantity step ,  woocommerce-quantity-step  ),
         placeholder        =>   ,
         desc_tip           =>  true ,
         description        => __(  Optional. Set quantity step  (a number greater than 0) ,  woocommerce  ),
         custom_attributes  => array(  step   =>  any ,  min    =>  1 ),
         value              => isset($values[ qty_step ]) && $values[ qty_step ] > 1 ? (int) $values[ qty_step ] : 1,
    ) );
    echo  </div> ;
}

// Show/hide setting fields (admin product pages)
add_action(  admin_footer ,  product_type_selector_filter_callback  );
function product_type_selector_filter_callback() {
    global $pagenow, $post_type;

    if( in_array($pagenow, array( post-new.php ,  post.php ) ) && $post_type ===  product  ) :
    ?>
    <script>
    jQuery(function($){
        if( $( input#qty_args ).is( :checked ) && $( div.qty-args ).hasClass( hidden ) ) {
            $( div.qty-args ).removeClass( hidden )
        }
        $( input#qty_args ).click(function(){
            if( $(this).is( :checked ) && $( div.qty-args ).hasClass( hidden )) {
                $( div.qty-args ).removeClass( hidden );
            } else if( ! $(this).is( :checked ) && ! $( div.qty-args ).hasClass( hidden )) {
                $( div.qty-args ).addClass( hidden );
            }
        });
    });
    </script>
    <?php
    endif;
}

// Save quantity setting fields values
add_action(  woocommerce_admin_process_product_object ,  wc_save_product_quantity_settings  );
function wc_save_product_quantity_settings( $product ) {
    if ( isset($_POST[ qty_unit ]) ) {
        $product->update_meta_data(  qty_unit , esc_attr($_POST[ qty_unit ]) );
    }

    if ( isset($_POST[ qty_args ]) ) {
        $values = $product->get_meta( _qty_args );

        $product->update_meta_data(  _qty_args , array(
             qty_min  => isset($_POST[ qty_min ]) && $_POST[ qty_min ] > 0 ? (int) wc_clean($_POST[ qty_min ]) : 0,
             qty_max  => isset($_POST[ qty_max ]) && $_POST[ qty_max ] > 0 ? (int) wc_clean($_POST[ qty_max ]) : -1,
             qty_step  => isset($_POST[ qty_step ]) && $_POST[ qty_step ] > 1 ? (int) wc_clean($_POST[ qty_step ]) : 1,
        ) );
    } else {
        $product->update_meta_data(  _qty_args , array() );
    }
}

// Display quantity unit in single product pages
add_action(  woocommerce_after_add_to_cart_quantity ,  display_product_selected_quantity_unit  );
function display_product_selected_quantity_unit() {
    global $product;

    $qty_unit = $product->get_meta( qty_unit );

    printf(  <span class="qty-unit">%s</span> , empty($qty_unit) ?  set  : $qty_unit ); 
}

// The quantity settings in action on front end
add_filter(  woocommerce_quantity_input_args ,  filter_wc_quantity_input_args , 99, 2 );
function filter_wc_quantity_input_args( $args, $product ) {
    if ( $product->is_type( variation ) ) {
        $parent_product = wc_get_product( $product->get_parent_id() );
        $values  = $parent_product->get_meta(  _qty_args  );
    } else {
        $values  = $product->get_meta(  _qty_args  );
    }

    if ( ! empty( $values ) ) {
        // Min value
        if ( isset( $values[ qty_min ] ) && $values[ qty_min ] > 1 ) {
            $args[ min_value ] = $values[ qty_min ];

            if( ! is_cart() ) {
                $args[ input_value ] = $values[ qty_min ]; // Starting value
            }
        }

        // Max value
        if ( isset( $values[ qty_max ] ) && $values[ qty_max ] > 0 ) {
            $args[ max_value ] = $values[ qty_max ];

            if ( $product->managing_stock() && ! $product->backorders_allowed() ) {
                $args[ max_value ] = min( $product->get_stock_quantity(), $args[ max_value ] );
            }
        }

        // Step value
        if ( isset( $values[ qty_step ] ) && $values[ qty_step ] > 1 ) {
            $args[ step ] = $values[ qty_step ];
        }
    }
    return $args;
}

// Ajax add to cart, set "min quantity" as quantity on shop and archives pages
add_filter(  woocommerce_loop_add_to_cart_args ,  filter_loop_add_to_cart_quantity_arg , 10, 2 );
function filter_loop_add_to_cart_quantity_arg( $args, $product ) {
    $values  = $product->get_meta(  _qty_args  );

    if ( ! empty( $values ) ) {
        // Min value
        if ( isset( $values[ qty_min ] ) && $values[ qty_min ] > 1 ) {
            $args[ quantity ] = $values[ qty_min ];
        }
    }
    return $args;
}

// The quantity settings in action on front end (For variable productsand their variations)
add_filter(  woocommerce_available_variation ,  filter_wc_available_variation_price_html , 10, 3);
function filter_wc_available_variation_price_html( $data, $product, $variation ) {
    $values  = $product->get_meta(  _qty_args  );

    if ( ! empty( $values ) ) {
        if ( isset( $values[ qty_min ] ) && $values[ qty_min ] > 1 ) {
            $data[ min_qty ] = $values[ qty_min ];
        }

        if ( isset( $values[ qty_max ] ) && $values[ qty_max ] > 0 ) {
            $data[ max_qty ] = $values[ qty_max ];

            if ( $variation->managing_stock() && ! $variation->backorders_allowed() ) {
                $data[ max_qty ] = min( $variation->get_stock_quantity(), $data[ max_qty ] );
            }
        }
    }

    return $data;
}

《刑法》生效。 网址是你的孩子主题(或gin)。 测试和工程。