js设计模式学习 --- 单例模式1

<script type="text/javascript">		
	var CreateDiv = function(html){
		this.html = html;
		this.init();
	};
	CreateDiv.prototype.init = function(){
		var div = document.createElement(‘div‘);
		div.innerHTML = this.html;
		document.body.appendChild(div);
	};	
	/*为了满足单一职责，这里引入代理*/
	var ProxySingletonCreateDiv = (function(){
		var instance;
		return function(html){
			if(!instance){
				instance = new CreateDiv(html);
			}			
			return instance;
		}
	})();
	
	var a = new ProxySingletonCreateDiv(‘11‘);
	var b = new ProxySingletonCreateDiv(‘22‘);
	alert(a===b);
</script>

var obj = {};

<script type="text/javascript">
	/*采用字面量创建*/
	var std = {
		foo: function(){
			alert (1);
		},
		bar:{
			str:‘hello world‘,
			say:function(){
				alert(this.str);
			}
		}
	};
	/*动态创建*/
	var com = {};
	com.namespace = function(name){
		var current = com,
			parts = name.split(‘.‘);				 
		for(var i in parts){
			if(!current[parts[i]]){
				current[parts[i]] = {};
			}
			current = current[parts[i]];
		}				 
	};
		
	com.namespace(‘demo‘);
	com.namespace(‘dom.style.display‘);
	console.log(com);
	/*相当于*/
	var com = {
		demo: {},
		dom: {
			style: {
				display:{}
			}
		}
	};
</script>

<script type="text/javascript">
	var user = (function(){
		var __name = ‘sven‘,
		__age = 29;
		return {
			getUserInfo: function(){
				return __name + ‘-‘ + __age;
			}
		}
	})();
</script>