7个WordPress常用代码段（Code Snippets）

运用代码段（Code Snippets）插件管理代码，可以不用额外安装更多插件，来解决WordPress建站过程中的一些常见功能需求，譬如安装Google analytics跟踪代码。下文中记录了我在搭建外贸网站和个人博客中常用到的代码段。

如何在WordPress文章/页面上禁止加载WooCommerce .Js（Javascript）和.Css文件？

woocommerce会在每个页面都默认加载几个css和js，这对网站速度是有影响的，将下面这段代码，在code snippets插件中添加一个新snippet，能够实现在除了购物车、结算、账户、产品以外的页面中，移除woocommerce的css和js。

/** Disable All WooCommerce  Styles and Scripts Except Shop Pages*/
add\_action( 'wp\_enqueue\_scripts', 'dequeue\_woocommerce\_styles\_scripts', 99 );
function dequeue\_woocommerce\_styles_scripts() {
if ( function\_exists( 'is\_woocommerce' ) ) {
if ( ! is\_woocommerce() && ! is\_cart() && ! is_checkout() ) {
# Styles
wp\_dequeue\_style( 'woocommerce-general' );
wp\_dequeue\_style( 'woocommerce-layout' );
wp\_dequeue\_style( 'woocommerce-smallscreen' );
wp\_dequeue\_style( 'woocommerce\_frontend\_styles' );
wp\_dequeue\_style( 'woocommerce\_fancybox\_styles' );
wp\_dequeue\_style( 'woocommerce\_chosen\_styles' );
wp\_dequeue\_style( 'woocommerce\_prettyPhoto\_css' );
# Scripts
wp\_dequeue\_script( 'wc\_price\_slider' );
wp\_dequeue\_script( 'wc-single-product' );
wp\_dequeue\_script( 'wc-add-to-cart' );
wp\_dequeue\_script( 'wc-cart-fragments' );
wp\_dequeue\_script( 'wc-checkout' );
wp\_dequeue\_script( 'wc-add-to-cart-variation' );
wp\_dequeue\_script( 'wc-single-product' );
wp\_dequeue\_script( 'wc-cart' );
wp\_dequeue\_script( 'wc-chosen' );
wp\_dequeue\_script( 'woocommerce' );
wp\_dequeue\_script( 'prettyPhoto' );
wp\_dequeue\_script( 'prettyPhoto-init' );
wp\_dequeue\_script( 'jquery-blockui' );
wp\_dequeue\_script( 'jquery-placeholder' );
wp\_dequeue\_script( 'fancybox' );
wp\_dequeue\_script( 'jqueryui' );
}
}
}

如何禁用WordPress的XML-RPC

WordPress站点很少需要启用XML-RPC，但是启用它可能会导致大量的安全问题。如果你使用WordPress应用程序，你才需要启用它。此代码片段将禁用XML-RPC以提高站点安全性。

add\_filter('xmlrpc\_enabled', '\_\_return\_false');

如何用代码段安装Google Analytics跟踪代码

请将从Google analytics中获取的跟踪代码放入到如下代码段中

add\_action( 'wp\_head', function () { ?>
	
这里粘贴Google Analytics的跟踪代码
<?php });

如何移除/隐藏WordPress评论中的Url字段

下面这段代码可以移除/隐藏部分WordPress主题中评论URL字段，如果你使用后发现不能移除，那说明主题不兼容，你可以在谷歌搜索：Remove Website field from the Comment Form in XXX theme，将XXX改为你的主题名称。

function remove\_comment\_fields($fields) {
unset($fields\['url'\]);
return $fields;
}
add\_filter('comment\_form\_default\_fields','remove\_comment\_fields');

譬如，在astra主题免费版中，隐藏评论的url字段使用下面的代码

function wpd\_remove\_comment\_website\_field( $fields ) {
    unset( $fields\['url'\] );
    
    return $fields;
}
add\_filter( 'comment\_form\_default\_fields', 'wpd\_remove\_comment\_website\_field', 99 );

在astra 主题付费版中，移除评论的url字段使用下面的代码

function wpd\_remove\_comment\_website\_field( $fields ) {
    unset( $fields\['url'\] );
    
    return $fields;
}
add\_filter( 'astra\_comment\_form\_default\_fields\_markup', 'wpd\_remove\_comment\_website\_field', 99 );

如何用代码段实现复制文章功能

下面这段代码可以给WordPress文章/自定义文章添加复制功能，在文章列表中会出现duplicate按钮，但不会给页面添加复制功能。使用它你可以省了一个复制文章功能插件。

/*
 * Function for post duplication. Dups appear as drafts. User is redirected to the edit screen
 */
function rd\_duplicate\_post\_as\_draft(){
  global $wpdb;
  if (! ( isset( $\_GET\['post'\]) || isset( $\_POST\['post'\])  || ( isset($\_REQUEST\['action'\]) && 'rd\_duplicate\_post\_as\_draft' == $\_REQUEST\['action'\] ) ) ) {
    wp_die('No post to duplicate has been supplied!');
  }
 
  /*
   * Nonce verification
   */
  if ( !isset( $\_GET\['duplicate\_nonce'\] ) || !wp\_verify\_nonce( $\_GET\['duplicate\_nonce'\], basename( \_\_FILE\_\_ ) ) )
    return;
 
  /*
   * get the original post id
   */
  $post\_id = (isset($\_GET\['post'\]) ? absint( $\_GET\['post'\] ) : absint( $\_POST\['post'\] ) );
  /*
   * and all the original post data then
   */
  $post = get\_post( $post\_id );
 
  /*
   * if you don't want current user to be the new post author,
   * then change next couple of lines to this: $new\_post\_author = $post->post_author;
   */
  $current\_user = wp\_get\_current\_user();
  $new\_post\_author = $current_user->ID;
 
  /*
   * if post data exists, create the post duplicate
   */
  if (isset( $post ) && $post != null) {
 
    /*
     * new post data array
     */
    $args = array(
      'comment\_status' => $post->comment\_status,
      'ping\_status'    => $post->ping\_status,
      'post\_author'    => $new\_post_author,
      'post\_content'   => $post->post\_content,
      'post\_excerpt'   => $post->post\_excerpt,
      'post\_name'      => $post->post\_name,
      'post\_parent'    => $post->post\_parent,
      'post\_password'  => $post->post\_password,
      'post_status'    => 'draft',
      'post\_title'     => $post->post\_title,
      'post\_type'      => $post->post\_type,
      'to\_ping'        => $post->to\_ping,
      'menu\_order'     => $post->menu\_order
    );
 
    /*
     * insert the post by wp\_insert\_post() function
     */
    $new\_post\_id = wp\_insert\_post( $args );
 
    /*
     * get all current post terms ad set them to the new post draft
     */
    $taxonomies = get\_object\_taxonomies($post->post\_type); // returns array of taxonomy names for post type, ex array("category", "post\_tag");
    foreach ($taxonomies as $taxonomy) {
      $post\_terms = wp\_get\_object\_terms($post_id, $taxonomy, array('fields' => 'slugs'));
      wp\_set\_object\_terms($new\_post\_id, $post\_terms, $taxonomy, false);
    }
 
    /*
     * duplicate all post meta just in two SQL queries
     */
    $post\_meta\_infos = $wpdb->get\_results("SELECT meta\_key, meta\_value FROM $wpdb->postmeta WHERE post\_id=$post_id");
    if (count($post\_meta\_infos)!=0) {
      $sql\_query = "INSERT INTO $wpdb->postmeta (post\_id, meta\_key, meta\_value) ";
      foreach ($post\_meta\_infos as $meta_info) {
        $meta\_key = $meta\_info->meta_key;
        if( $meta\_key == '\_wp\_old\_slug' ) continue;
        $meta\_value = addslashes($meta\_info->meta_value);
        $sql\_query\_sel\[\]= "SELECT $new\_post\_id, '$meta\_key', '$meta\_value'";
      }
      $sql\_query.= implode(" UNION ALL ", $sql\_query_sel);
      $wpdb->query($sql_query);
    }
 
 
    /*
     * finally, redirect to the edit post screen for the new draft
     */
    wp\_redirect( admin\_url( 'post.php?action=edit&post=' . $new\_post\_id ) );
    exit;
  } else {
    wp\_die('Post creation failed, could not find original post: ' . $post\_id);
  }
}
add\_action( 'admin\_action\_rd\_duplicate\_post\_as\_draft', 'rd\_duplicate\_post\_as_draft' );
 
/*
 * Add the duplicate link to action list for post\_row\_actions
 */
function rd\_duplicate\_post_link( $actions, $post ) {
  if (current\_user\_can('edit_posts')) {
    $actions\['duplicate'\] = '<a href="' . wp\_nonce\_url('admin.php?action=rd\_duplicate\_post\_as\_draft&post=' . $post->ID, basename(\_\_FILE\_\_), 'duplicate_nonce' ) . '" title="Duplicate this item" rel="permalink">Duplicate</a>';
  }
  return $actions;
}
 
add\_filter( 'post\_row\_actions', 'rd\_duplicate\_post\_link', 10, 2 );

如何用代码段禁止WordPress自动生成图片

由于每张图片在上传到WordPress时，会被WordPress或部分插件自动生成很多不同尺寸的图片，针对用不上的图片尺寸，可以用短代码直接组织系统生成图片，不仅能节省空间，也能避免消耗压缩额度，下面介绍如何用代码段（code snippets）禁止WordPress自动生成图片。

需要知道的是，这些自动生成的图片并不能在Wordpress的媒体库看到，需要在服务器的文件夹中查看。

下图是Siteground后台查看图片文件的方法，请在进入网站的Sitetools后按下图所示顺序操作查看，我们能看到系统为同一张图生成了很多不同尺寸的图片。

在网站页面设计完、内容上传前，我们先禁止所有自动生成的图片；若马上可以上传内容了，我们可以根据设计情况，酌情放开部分图片尺寸，譬如在制作产品列表页时，我们用到了300*300px的图片，那么就在下面的代码中，将对应行的代码前加//注释掉或直接删除该行。

// disable generated image sizes
function shapeSpace_disable_image_sizes($sizes) {
	
	unset($sizes['thumbnail']);    // disable thumbnail size
	unset($sizes['medium']);       // disable medium size
	unset($sizes['large']);        // disable large size
	unset($sizes['medium_large']); // disable medium-large size
	unset($sizes['1536x1536']);    // disable 2x medium-large size
	unset($sizes['2048x2048']);    // disable 2x large size
   unset($sizes['shop_catalog']);
   unset($sizes['shop_single']);
   unset($sizes['shop_thumbnail']);
   unset($sizes['woocommerce_thumbnail']);
   unset($sizes['woocommerce_single']);
   unset($sizes['woocommerce_gallery_thumbnail']);
	
	return $sizes;
	
}
add_action('intermediate_image_sizes_advanced', 'shapeSpace_disable_image_sizes');

// disable scaled image size
add_filter('big_image_size_threshold', '__return_false');

// disable other image sizes
function shapeSpace_disable_other_image_sizes() {
	
	remove_image_size('post-thumbnail'); // disable images added via set_post_thumbnail_size() 
	remove_image_size('another-size');   // disable any other added image sizes
	
}
add_action('init', 'shapeSpace_disable_other_image_sizes');

如何用代码段去掉Woocommerce产品首页、列表页的面包屑

/**
 * Remove the breadcrumbs 
 */
add\_action( 'init', 'woo\_remove\_wc\_breadcrumbs' );
function woo\_remove\_wc_breadcrumbs() {
    remove\_action( 'woocommerce\_before\_main\_content', 'woocommerce_breadcrumb', 20, 0 );
}

本文原文由LOYSEO 发布，LOYSEO专注于WordPress、Elementor、外贸建站教程。