如何在Local Storage中存储对象数组？

This is my code. I am trying since a couple of days to create an Array of Objects, which I will then store in Local Storage. Here is the problem, I need to first Get the existing value from Local Storage.

这是我的代码。我正在尝试创建一个对象数组，然后将其存储在本地存储中。这是问题，我需要先从Local Storage获取现有值。

I then need to add the new data object to the existing array. I then convert it into JSON so that I can store it back in the local storage.

然后我需要将新数据对象添加到现有数组中。然后我将其转换为JSON，以便我可以将其存储在本地存储中。

onRegisterSubmit(){
    const user = {
        a: this.a,
        b: this.b,
        c: this.c,
      id: Date.now()
    }    

   var abc = [];
   var get =  JSON.parse(localStorage.getItem('user'));
   abc = [get];
   abc.push(user);

   localStorage.setItem('user', JSON.stringify(abc));

   console.log(JSON.stringify(abc));
   console.log(get);
  }

I want the JSON to be an array of objects like this,

我希望JSON是这样的对象数组，

[{"hour":1,"minute":21,"ampm":"PM","repeatDays":[],"message":"","todayOrTomorrow":"Tomorrow","isRepeatMode":false,"isEnabled":false,"id":"1493797882440"},{"hour":1,"minute":24,"ampm":"PM","repeatDays":[],"message":"","todayOrTomorrow":"Tomorrow","isRepeatMode":false,"isEnabled":false,"id":"1493797896257"},{"hour":6,"minute":14,"ampm":"PM","repeatDays":[],"message":"","todayOrTomorrow":"Tomorrow","isRepeatMode":false,"isEnabled":false,"id":"1493815470408"}]

This is my JSON.

这是我的JSON。

[[[[[[[{"id":1493820594019},{"id":1493820606448}],{"id":1493820609111}],{"id":1493820610150}],{"id":1493820610553}],{"id":1493820610827}],{"id":1493820611015}],{"id":1493820612018}]

I've been trying for several days and any help will be greatly appreciated.

我已经尝试了几天，任何帮助将不胜感激。

3 个解决方案

#1

The issues with that code are:

该代码的问题是：

You're wrapping the result you get in an array, but in theory, you want to already have an array.

您将结果包装在数组中，但理论上，您希望已经有一个数组。
~~You're storing user, not get or abc.~~ (You removed that with an edit.)

你是存储用户，而不是获取或abc。（您通过编辑删除了它。）

To store the array, do what you're doing:

要存储数组，请执行您正在执行的操作：

localStorage.setItem("users", JSON.stringify(users));

To get the array:

要获得数组：

users = JSON.parse(localStorage.getItem("users") || "[]");

Note how that provides a default (empty array) if getItem returns null because we've never stored our users there.

请注意，如果getItem返回null，那么它是如何提供默认值（空数组）的，因为我们从未在那里存储过我们的用户。

To add a user to the array:

要将用户添加到阵列：

users.push({id: 1, foo: "bar"});

Example (live on jsFiddle [Stack Snippets don't allow local storage]):

示例（live on jsFiddle [Stack Snippets不允许本地存储]）：

(function() { // Scoping function to avoid creating globals
    // Loading
    var users = JSON.parse(localStorage.getItem("users") || "[]");
    console.log("# of users: " + users.length);
    users.forEach(function(user, index) {
        console.log("[" + index + "]: " + user.id);
    });

    // Modifying
    var user = {
        id: Math.floor(Math.random() * 1000000)
    };
    users.push(user);
    console.log("Added user #" + user.id);

    // Saving
    localStorage.setItem("users", JSON.stringify(users));
})();

That shows you the list of current users in the console, adding one each time you refresh the page.

这会显示控制台中当前用户的列表，每次刷新页面时都会添加一个用户。

#2

Try something like this:- link https://jsfiddle.net/sureshraina/nLexkyfw/1/

尝试这样的事情： - 链接https://jsfiddle.net/sureshraina/nLexkyfw/1/

var mydatas = new Array();
        mydatas[0] = "data";
        mydatas[1] = "data1";
        mydatas[2] = "data2";

        localStorage["mydatas"] = JSON.stringify(mydatas);

        var datas = JSON.parse(localStorage["mydatas"]);

#3

See this post.

看这篇文章。

You can't store Objects, you have to store a String. So the workaround is to stringify your Object before you store it (for example, you could use change it to a JSON object, store it, and read it again when needed).

你不能存储对象，你必须存储一个字符串。因此，解决方法是在存储对象之前对其进行字符串化（例如，您可以将其更改为JSON对象，存储它，并在需要时再次读取它）。

#1