JS模式之发布/订阅模式

<script type="text/javascript">

var pubsub = {};

(function($) {

$.topics = {};

// 发布或广播事件
$.publish = function (topic, args) {
if (!$.topics[topic])
return false;
if ($.topics[topic] instanceof Array) {
var topics = $.topics[topic];
for(var i = 0; i < topics.length; i++)
topics[i](args);
}

return this;
};

// 通过特定名称和回调函数订阅事件
$.subscribe = function (topic, func) {
if (!$.topics[topic])
$.topics[topic] = [];
// 对应topic下加入回调函数
$.topics[topic].push(func);
return this;
};

// 解绑取消订阅事件
$.unsubscribe = function (topic) {
if (!$.topics[topic])
return false;
delete($.topics[topic]);
return this;
}

})(pubsub);

// 注册confirm事件
pubsub.subscribe("confirm", function() {
alert("this is the confirm");
});

// 注册alert事件 并订阅该事件后取消该订阅
pubsub.subscribe("alert", function(data) {
alert("this is the alert " + data);
}).publish("alert", "success").unsubscribe("alert");

</script>