## subscribe ##### Description Subscribe to channels. Warning: this function will probably change in the future. 方法回调函数,注意：该方法在将来有可能被修改。 ##### Parameters *channels*: an array of channels to subscribe to *callback*: either a string or an array($instance, 'method\_name'). The callback function receives 3 parameters: the redis instance, the channel name, and the message. ##### Example ``` <pre class="calibre9">function f($redis, $chan, $msg) { switch($chan) { case 'chan-1': ... break; case 'chan-2': ... break; case 'chan-2': ... break; } } $redis->subscribe(array('chan-1', 'chan-2', 'chan-3'), 'f'); // subscribe to 3 chans ```