PHP - 使用静态函数的Namespaced插件

Question

I'm trying to namespace my plugin functions by using a class and static functions. I'm getting the error:

Fatal error: Constructor Read_Time::read_time() cannot be static in /Applications/MAMP/htdocs/Wordpress/wp-content/plugins/readtime/readtime.php on line 41

class Read_Time {
public $options;

static public function init() {
    add_filter('wp_meta', __CLASS__ . '::post_text');
}

static private function post_text() {
    if(is_single()) {
        global $post;
        $content = $post->post_content;
        echo("<h1>" . self::read_time($content) . "</h1>");
    }
}

static private function word_count($to_count) {
    return str_word_count($to_count);       
}

static private function read_time($content) {
    $wpm = 200;
    $int_minutes = ceil( self::word_count($content) / $wpm );
    if($int_minutes == 1) {
        return $int_minutes . " minute";
    } 
    else {
        return $int_minutes . " minutes";
    }       
}
}       
add_action('init', 'Read_Time::init');

Can someone tell me what I'm doing wrong?

Answer 1

PHP is interpreting your method read_time as a constructor for the class Read_Time, because it is not case-sensitive. The constructor cannot be static.

From the online documentation:

As of PHP 5.3.3, methods with the same name as the last element of a namespaced class name will no longer be treated as constructor. This change doesn't affect non-namespaced classes.

Example #2 Constructors in namespaced classes

<?php
namespace Foo;
class Bar {
    public function Bar() {
        // treated as constructor in PHP 5.3.0-5.3.2
        // treated as regular method as of PHP 5.3.3
    }
}
?>

P.S. If you really are using a version of PHP < 5.3.3, you should strongly consider upgrading. A lot has changed, and older versions may have unpatched bugs.