php - "double underscore"和 "underscore x"有什么区别？

Question

在 PHP 中，特别是在 Wordpress 中，__('string') 和 _x('string') 有什么区别？

我正在阅读 Wordpress 文档并感到困惑。以下混淆的好例子来自 Wordpress doc 上的示例代码对于 register_post_type():

$labels = array(
    'name'               => _x( 'Books', 'post type general name', 'your-plugin-textdomain' ),
    'singular_name'      => _x( 'Book', 'post type singular name', 'your-plugin-textdomain' ),
    'menu_name'          => _x( 'Books', 'admin menu', 'your-plugin-textdomain' ),
    'name_admin_bar'     => _x( 'Book', 'add new on admin bar', 'your-plugin-textdomain' ),
    'add_new'            => _x( 'Add New', 'book', 'your-plugin-textdomain' ),
    'add_new_item'       => __( 'Add New Book', 'your-plugin-textdomain' ),
    'new_item'           => __( 'New Book', 'your-plugin-textdomain' ),
    'edit_item'          => __( 'Edit Book', 'your-plugin-textdomain' ),
    'view_item'          => __( 'View Book', 'your-plugin-textdomain' ),
    'all_items'          => __( 'All Books', 'your-plugin-textdomain' ),
    'search_items'       => __( 'Search Books', 'your-plugin-textdomain' ),
    'parent_item_colon'  => __( 'Parent Books:', 'your-plugin-textdomain' ),
    'not_found'          => __( 'No books found.', 'your-plugin-textdomain' ),
    'not_found_in_trash' => __( 'No books found in Trash.', 'your-plugin-textdomain' )
);

Answer 1

在WordPress中，_x()和__()都是翻译函数。 _x() 允许您为翻译指定上下文:

<?php _x( $text, $context, $domain ); ?>

而 __() 不会:

<?php __( $text, $domain ); ?>

上下文选项在直译可能无法产生预期结果的各种情况下很有用。

Since the string 'Read' on its own could have one of several different meanings in English, context is given so that translators know that they should be supplying a short term that means "Books I have read."

一些其他示例可能是:“日期”、“类型”、“正确”、“叶子”等。

来源:WordPress Codex