Simulating emmiter custom events in nodejs
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script>
function Emitter() {
this.events = {}; //存放事件的地方
}
Emitter.prototype.on = function(type, cb) {
var events = this.events;
events = events[type] = events[type] || [];
events.push(cb);
};
Emitter.prototype.emit = function(type) {
var args = [].slice.call(arguments, 1);
var cbs = this.events[type], cb;
while (cb = cbs && cbs.shift()) {
cb.apply(this, args);
}
};
var emitter = new Emitter();
emitter.on('customevent', function(param) {
alert(param);
});
emitter.on('customevent', function() {
alert(1);
});
emitter.emit('customevent', 'xxx');
</script>
</head>
<body>
</body>
</html>
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