index.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<script>
// json的简写方式
let name = 'tom';
let age = 18;
let json = {
name, // name:name,
age, // age:age
/*
show:function (){
return this.name;
}
*/
show(){
return this.name;
}
};
console.log(json); // {name: "tom", age: 18}
console.log(json.show()); //tom
// Obiect.is 比较来两个值是否相等
console.log(NaN == NaN); //false
console.log(Object.is(NaN,NaN)); //true
console.log(+0 == -0); //true
console.log(Object.is(+0,-0)); //false
// Object.assign 用来合并对象的
// Object.assign 合并对象
let json1 = {a:1};
let json2 = {b:2};
let json3 = {c:3};
let newjson = Object.assign({},json1,json2,json3); // {a: 1, b: 2, c: 3}
console.log(newjson);
// Object.assign 可以赋值数组
let arr1 = [1,2,3];
let newarr = Object.assign([],arr1);
console.log(newarr);
// Object.keys 循环字段
// Object有keys, values, entries三个处理循环的方法
let json4 = {
name:'tom',
age:18,
sex:'男'
};
for(let key of Object.keys(json4)){
console.log(key); // name age sex
};
// 对Object对象进行解构
let {keys, values, entries} = Object;
for(let key of keys(json4)){
console.log(key); // name age sex
};
for(let key of values(json4)){
console.log(key); // tom 18 男
};
for(let key of entries(json4)){
console.log(key);
// (2) ["name", "tom"]
// (2) ["age", 18]
// (2) ["sex", "男"]
};
for(let [key,val] of entries(json4)){
console.log(key,val);
// name tom
// age 18
// sex 男
};
// 三个点解构对象
let {x,y,...z} = {x:"apple",y:"banana",c:"orange",d:1,e:2};
console.log(x,y,z); // apple banana {c: "orange", d: 1, e: 2}
// 快速复制一个对象
let json5 = {
a:1,
b:2
};
let newjson5 = {...json5};
console.log(newjson5); // {a: 1, b: 2}
</script>
</body>
</html>
