javascript遍历对象的五种方式实例代码

var notEnum = Symbol("继承不可枚举symbol");
var proto = {
    [Symbol("继承可枚举symbol")]: "继承可枚举symbol",
    name: "继承可枚举属性"
};
// 不可枚举属性
Object.defineProperty(proto, "age", {
    value: "继承不可枚举属性"
});
// 不可枚举symbol属性
Object.defineProperty(proto, notEnum, {
    value: "继承不可枚举symbol"
});

var obj = {
    job1: "自有可枚举属性1",
    job2: "自有可枚举属性2",
    [Symbol("自有可枚举symbol")]: "自有可枚举symbol"
};
// 继承
Object.setPrototypeOf(obj, proto);
// 不可枚举属性
Object.defineProperty(obj, "address", {
    value: "自有不可枚举属性"
});
// 不可枚举symbol属性
var ownNotEnum = Symbol("自有不可枚举symbol");
Object.defineProperty(obj, ownNotEnum, {
    value: "自有不可枚举symbol"
});

for(var attr in obj){
    console.log(attr,"==",obj[attr]);
}

Object.keys(obj).map((attr)=>{
    console.log(attr,"==",obj[attr]);
});

Object.getOwnPropertyNames(obj).map((attr)=>{
    console.log(attr,"==",obj[attr]);
});

Object.getOwnPropertySymbols(obj).map((attr)=>{
    console.log(attr,"==",obj[attr]);
});

Reflect.ownKeys(obj).map((attr)=>{
    console.log(attr,"==",obj[attr]);
});

Object.values(obj).map((val)=>{
    console.log(val);
});

Object.entries(obj).map((val)=>{
    console.log(val);
});

for(var attr in obj){
    if(Object.prototype.hasOwnProperty.call(obj,attr)){
        console.log("自有属性：：",attr);
    }else{
        console.log("继承属性：：",attr);
    }
}

Reflect.ownKeys(obj).map((attr) => {
    if (Object.prototype.propertyIsEnumerable.call(obj, attr)) {
        console.log("可枚举属性：：", attr);
    } else {
        console.log("不可枚举属性：：", attr);
    }
});