ES6语法学习笔记之对象简洁语法，及新增内容

对象简洁语法

		let name="suosuo";
		let age=18;
		let json={
			name,//name:name
			age,//age:age
			// showA:function(){
			// 	return this.name;
			// }

			showA(){
				return this.name;
			};//是上面一种的简写
		};
		console.log(json);//{name: "suosuo", age: 18, showA: ƒ}
		console.log(json.showA());

		let x=1;
		let y=10;

		function show({x,y}){
			console.log(x,y);
		}
		show({x:1,y:10});
		//因为上面有赋值，所以可以简写为如下：
		show({x,y});

新增内容

Object.is(对比内容一，对比内容二)

只要二者长得一样，结果就一定是true，比如NaN

		console.log(NaN==NaN);//原来是false

		console.log(Number.isNaN(NaN));//true,这里限定了NaN的类型是数字才是true

		console.log(Object.is(NaN,NaN));//true

		console.log(+0==-0);//true

		console.log(Object.is(+0,-0));//false

		console.log(Object.is(+0,-0));//false

Object.assign(新的对象比如{},合并对象一，合并对象二……)用来合并对象

		let json ={a:1};
		let json2 = {b:2};
		let json3 = {c:3};
		let obj = Object.assign({},json,json2,json3);
		console.log(obj);	//a: 1
							// b: 2
							// c: 3
							// __proto__: Object

		//如果在json2中加一个a:5，结果中的a将会变成5

		let arr = ['apple','banana','orange'];
		let arr2 = Object.assign([],arr);
		arr2.push('tomato');
		console.log(arr2);//"apple", "banana", "orange", "tomato"]

Object.keys() Object.values() Object.entries()

		// let json4={
		// 	d:1,
		// 	e:2,
		// 	f:3
		// };
		// for (let key of Object.keys(json4)){
		// 	console.log(key);//d e f
		// };

		let {keys,values,entries} = Object;

		let json4={
			d:1,
			e:2,
			f:3
		};

		for(let key of Object.keys(json4)){
			console.log(key);//d e f如下都把object省略了，意义一样
		};

		for (let value of values(json4)){
			console.log(value);//1 2 3
		};

		for(let item of entries(json4)){
			console.log(item);//每一个选项如d:1都被拆分成一个length为2的数组
		}

		for(let [key,val] of entries(json4)){
			console.log(key,val);
		};

...也可以用在对象身上

		let {x,y,...z}={x:1,y:2,a:3,b:4};
		console.log(x,y,z);


		let json1 = {a:3,b:4};
		let json2 ={...json1};
		// delete json2.b;
		console.log(json2);//{a: 3, b: 4}加了上一行就只剩下a