如何通过 Index 或 JavaScript 中的任何其他可能方式访问对象内部存在的数组元素

Question

基本上我试图在JavaScript中访问对象的属性，并且比我想的要 如果我可以访问对象中存在的数组值

// Object
let user={
name:"rajat",
age:23,
email:["ag.112","ag.113"]
};

现在为了访问数组的特定元素，我无法理解如何做到这一点

console.log(user);
console.log(user.name);
console.log(user.age);
console.log(user['age']);

就像我想在 JavaScript 中访问电子邮件中存在的第二个元素(ag.113(

Answer 1

我不知道这是否是你的意思，但你可以这样做：

numb = 0/1
user.email[numb]

获取"电子邮件"的内容; 或者你可以做

user[email][numb]

我写了一个简单的函数来处理这些简单并将它们放入本地存储中：

function getlist(option, name, listid, must, childnam, contenta, contentb) {
if (list != 1) {
if (option != "help") {
var listid = "produkte";
var list = JSON.parse(localStorage.getItem(listid));
console.log(list)
var allleng = _.size(list);
console.log(cont);
switch (option) {
default: var child = list;
return child;
break;
case "get":
var child = list[name];
return child;
break;
case "pardel":
var child = list[name];
var leng = _.size(child);
var cont = child[childnam];
delete list[name];
localStorage.setItem(listid, JSON.stringify(list));
return list;
break;
case "setpar":
list = _.extend(list, _.object([
[contenta, {}]
]));
localStorage.setItem(listid, JSON.stringify(list));
return list;
break;
case "set":
list = _.extend(list, _.extend(list[name], _.object([
[childnam, contenta],
[(childnam + "must"), must]
])));
localStorage.setItem(listid, JSON.stringify(list));
return list;
break;
case "setchild":
list[name] = _.extend(list, _.extend(list[name], _.object([
[childnam, _.object([
[contenta, contentb],
[(contenta + "must"), must]
])]
])));
localStorage.setItem(listid, JSON.stringify(list));
return list;
break;
case "length":
var child = list[name];
var leng = _.size(child);
var cont = child[childnam];
return leng;
break;
case "parlength":
var child = list[name];
var leng = _.size(child);
var cont = child[childnam];
return _.size(list);
break;
case "childlength":
var child = list[name];
var leng = _.size(child);
var cont = child[childnam];
return _.size(list[name][childnam]);
break;
case "childdel":
var child = list[name];
var leng = _.size(child);
var cont = child[childnam];
delete list[name][childnam][contenta];
localStorage.setItem(listid, JSON.stringify(list));
return list;
break;
case "del":
var child = list[name];
var leng = _.size(child);
var cont = child[childnam];
delete list[name][childnam];
localStorage.setItem(listid, JSON.stringify(list));
return list;
break;
case "getchild":
var child = list[name];
var leng = _.size(child);
var cont = child[childnam];
return list[name][childnam];
break;
case "getpar":
return list;
break;
}
} else {
console.log("getpar: gibt alle Arten an Produkten aus");
console.log("get: gibt den ersten inhalt aus");
console.log("getchild:");
console.log("pardel:");
console.log("del:");
console.log("set:");
console.log("setchild:");
console.log("setpar:");
console.log("parlength:");
console.log("childlength:");
console.log("length:");
console.log("help: hilfe!! lasst mich hier raus!!!");
}
} else {}
}