function deepCopy(obj){
    //判斷是否是簡(jiǎn)單數(shù)據(jù)類型，
    if(typeof obj == "object"){
        //復(fù)雜數(shù)據(jù)類型
        var result = obj.constructor == Array ? [] : {};
        for(let i in obj){
            result[i] = typeof obj[i] == "object" ? deepCopy(obj[i]) : obj[i];
        }
    }else {
        //簡(jiǎn)單數(shù)據(jù)類型 直接 == 賦值
        var result = obj;
    }
    return result;
}

乞丐版

 var newObj = JSON.parse( JSON.stringify( someObj ) );