桥接模式

<?php /**桥接模式用户之间发送信息，站内信息、短信、email、手机....*/interface msg{public function send($to, $content);}class zn implements msg {public function send($to, $content){echo "站内信", $to, "内容", $content;}}class email implements msg {public function send($to, $content){echo "email", $to, "内容", $content;}}class sms implements msg {public function send($to, $content){echo "sms", $to, "内容", $content;}}//内容也细分了普通，加急，特急//由于我们只能扩展，不能修改，所以再添加的类话就添加的太多了。一共9个/*class zncommon implements msgclass znwarm implements msgclass zndanger implements msg......*/<====================================================================================================================><?php //解决方案//设计模式的目的就是解耦，但是不能完美。所以会有桥接模式。适当耦合！1//如果按照上面的方式，需要创建 m*n 个类。下面只需要 m+n  个就行 。防止子类爆炸的情况abstract class info {protected $send = null;public function __construct($send){$this->send = $send;}abstract public function msg($content);public function send($to, $content){$content = $this->msg($content);return $this->send->send($to, $content);}}class commoninfo extends info {public function msg($content) {return $content.'<br />普通';}}class warninfo extends info {public function msg($content) {return $content.'<br />紧急';}}class dangerinfo extends info {public function msg($content) {return $content.'<br />特急';}}class zn {public function send($to, $content){return "站内信给".$to."<br />内容是:".$content;}}class email {public function send($to, $content){return "email".$to."<br />内容是:".$content;}}class sms {public function send($to, $content){return "email".$to."<br />内容是:".$content;}}//使用站内发普通信息$commoninfo = new commoninfo(new zn());echo $commoninfo->send('小东','水电费');echo "<hr />";//使用短信发特急信息$dangerinfo = new dangerinfo(new sms());echo $dangerinfo->send('上帝','保佑我，心想事成！');