Wordpress Title, Keywords and Description SEO

虽然市面上有很不错的 WordPress 标题 SEO 插件：All in One SEO Pack, HeadSpace 2 等, 但是我还是喜欢折腾用代码的方式去控制 WP 的 标题, 标签及描述等的SEO.

1. 我的 WordPress Title SEO 方式是在主题文件 header.php 里面写入下面的代码

<title><?php if (is_home()) {bloginfo('name');} else {echo trim(wp_title('',0));}?></title>

2. WordPress 关键词及描述

<?php
     //判断是否为首页
    if ( is_home ( ) )
    {
      $description = "英文SEO, 致力于Google, Yahoo, Bing and Baidu 等搜索引擎优化(SEO) 及折腾 WordPress, Drupal, ECMS！";
      $keywords = "英文SEO,Google SEO,Yahoo SEO,Bing SEO,Baidu SEO,搜索引擎优化";
    }
     //判断是否为文章页
    else if ( is_single () )
    {
      $description = wp_title(",",false,right).mb_substr(strip_tags($post->post_content),0,120,$encoding="UTF-8");
       //$description = mb_strimwidth(strip_tags(apply_filters('the_content',$post->post_content)),0,120);
      $keywords = "";
      $tags = wp_get_post_tags($post->ID);
      foreach ($tags as $tag ) {
      $keywords = $keywords . $tag->name . ",";
      }
      }
     //判断是否为分类页
    else if ( is_category( ) )
    {
      $description = strip_tags(category_description());
      $keywords = single_cat_title("", false);
    }
     //判断是否为标签页
    else if ( is_tag() )
    {
       $description = single_tag_title('SurDA',false);
       $description = "这里是标签[".$description."]下的所有文章";
       $keywords = single_tag_title('SurDA',false);
    }

    //其他都显示文章标题
    else {
        $description = wp_title("",false);
        $keywords = wp_title("",false);
    }
?>
<meta name="description" content="<?php echo $description ; ?>" />
<meta name="keywords" content="<?php echo $keywords ; ?>" />

3. 最后一步就是在主题的 Functions.php 中添加描述截取数及输出为utf-8的代码

if (!function_exists('mb_substr')) {
    function mb_substr($str, $start, $len = '', $encoding="UTF-8"){
        $limit = strlen($str);

        for ($s = 0; $start > 0;–$start) {// found the real start
            if ($s >= $limit)
                break;

            if ($str[$s] <= "\x7F")
                ++$s;
            else {
                ++$s; // skip length

                while ($str[$s] >= "\x80" && $str[$s] <= "\xBF")
                    ++$s;
            }
        }

        if ($len == '')
            return substr($str, $s);
        else
            for ($e = $s; $len > 0; –$len) {//found the real end
                if ($e >= $limit)
                    break;

                if ($str[$e] <= "\x7F")
                    ++$e;
                else {
                    ++$e;//skip length

                    while ($str[$e] >= "\x80" && $str[$e] <= "\xBF" && $e < $limit)
                        ++$e;
                }
            }
        return substr($str, $s, $e – $s);
    }
}

OK, 搞定. 参考了 SurDA 的 Google Html建议 短的元说明 修善办法.