WordPress通过图片URL地址获取 ID

WordPress图片编有ID号，存放在postmeta表中。通过图片URL地址获取ID的需求在对图片进行重定义等操作中会使用到。

function monseng_get_attachment_id ($img_url) {

	$cache_key	= md5($img_url);

	$post_id	= wp_cache_get($cache_key, 'monseng_attachment_id' );

	if($post_id == false){

		$attr		= wp_upload_dir();

		$base_url	= $attr['baseurl']."/";

		$path = str_replace($base_url, "", $img_url);

		if($path){

			global $wpdb;

			$post_id	= $wpdb->get_var("SELECT post_id FROM $wpdb->postmeta WHERE meta_value = '{$path}'");

			$post_id	= $post_id?$post_id:'';

		}else{

			$post_id	= '';

		}

		wp_cache_set( $cache_key, $post_id, 'monseng_attachment_id', 86400);

	}

	return $post_id;

}

调用方法：

#现在前往