JS/03_浅拷贝与深拷贝.html at master · ymgaoski/JS · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>浅拷贝与深拷贝</title>

  <script>

	(function (){
		// 原对象
		var p1 = {
			name : 'xgao',
			age : 18,
			like : ['读书','玩','音乐']
		};

		// 深拷贝
		var p3 = {};
		this.deepCopy(p1,p3);
		p3.name = 'wang';
		p3.age = 38;
		p3.like.push('吃');
		console.log(p3,'深拷贝 p3');

		// 浅拷贝
		var p2 = {};
		// ES6方法，将p1拷贝到p2
		Object.assign(p2,p1);
		// 自定义方法
		// this.lightCopy(p1,p2);

		p2.name = 'qiang';
		p2.age = 29;
		p2.like.push('游戏');
		console.log(p2,'浅拷贝 p2');


		console.log(p1,'原始 p1');
	})();


	/**
	* 浅拷贝
	* @param {原始对象} sourceObj
	* @param {新对象} disObj
	*/
	function lightCopy(sourceObj,disObj){
	  for(let i in sourceObj){
		disObj[i] = sourceObj[i];
	  }
	}

	/**
	* 深拷贝
	* @param {原始对象} sourceObj
	* @param {新对象} disObj
	*/
	function deepCopy(sourceObj,disObj){

	    for(let i in sourceObj){

			if (!this.isObj(sourceObj[i])){
				// 基础类型，值类型，直接赋值
				disObj[i] = sourceObj[i];
			}else{
				// 复杂类型，引用类型，需要创建新对象再赋值, 下面这个 new constructor 才是关键
				let newObj = new sourceObj[i].constructor;
				this.deepCopy(sourceObj[i],newObj);

				// 设置新对象
				disObj[i] = newObj;
			}
	    }
	}
	// 是否是对象
	function isObj(obj){
		return obj instanceof Object;
	}

  </script>

</head>
<body>
  <h1>浅拷贝与深拷贝</h1>
</body>
</html>