我正在使用节点的eventemitter,尽管其他事件库建议是受欢迎的.
如果触发几个事件,我想运行一个函数.应该听多个事件,但是如果任何一个事件触发,它们都被删除.希望这个代码示例演示了我正在寻找什么.
var game = new eventEmitter();
game.once(['player:quit','player:disconnect'],function () {
endGame()
});
最干净的处理方式是什么？
解决方法
“扩展”EventEmitter,如下所示：
var EventEmitter = require('events').EventEmitter;
EventEmitter.prototype.once = function(events,handler){
// no events,get out!
if(! events)
return;
// Ugly,but helps getting the rest of the function
// short and simple to the eye ... I guess...
if(!(events instanceof Array))
events = [events];
var _this = this;
var cb = function(){
events.forEach(function(e){
// This only removes the listener itself
// from all the events that are listening to it
// i.e.,does not remove other listeners to the same event!
_this.removeListener(e,cb);
});
// This will allow any args you put in xxx.emit('event',...) to be sent
// to your handler
handler.apply(_this,Array.prototype.slice.call(arguments,0));
};
events.forEach(function(e){
_this.addListener(e,cb);
});
};
我在这里创造了一个要点：https://gist.github.com/3627823
其中包括一个示例(您的示例,有一些日志)
[UPDATE]
以下是对我的执行情况的一次调整,只会根据评论中的要求删除被调用的事件：
var EventEmitter = require('events').EventEmitter;
EventEmitter.prototype.once = function(events,but helps getting the rest of the function
// short and simple to the eye ... I guess...
if(!(events instanceof Array))
events = [events];
var _this = this;
// A helper function that will generate a handler that
// removes itself when its called
var gen_cb = function(event_name){
var cb = function(){
_this.removeListener(event_name,cb);
// This will allow any args you put in
// xxx.emit('event',...) to be sent
// to your handler
handler.apply(_this,0));
};
return cb;
};
events.forEach(function(e){
_this.addListener(e,gen_cb(e));
});
};
我发现node.js在EventEmitter中已经有一个方法：check here the source code,但这可能是最近的一个补充.
