SOURCE

function deepClone(obj){
    //只考虑数组和对象
    if(typeof obj !== 'object' || obj === null) return obj;
    let result = obj instanceof Array ? []:{};
    for(let key in obj){
        if(obj.hasOwnProperty(key)){
            result[key]= deepClone(obj[key])
        }     
    }
    return result;
}
let obj = {
    a:'1212',
    c:[1,3,5],
    d:{
        e:'333',
        f:{
            g:'ooo'
        }
    }
}

let newObj = deepClone(obj);
console.log(newObj);