将新数组元素添加到JSON对象

Question

我有一个JSON格式对象，我从一个名为teamJSON的变量中的JSON文件中读取，如下所示：

 {"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}

我想在数组中添加一个新项，例如

{"teamId":"4","status":"pending"}

结束

{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"},{"teamId":"4","status":"pending"}]}

在写回文件之前。添加到新元素的好方法是什么？我接近但所有双引号都被逃脱了。我已经找到了一个很好的答案，但没有一个完全覆盖这个案例。任何帮助表示赞赏。

Answer 1

JSON只是一种表示法;要进行更改，你需要parse它，以便你可以将更改应用于本机JavaScript对象，然后stringify回到JSON

var jsonStr = '{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}';

var obj = JSON.parse(jsonStr);
obj['theTeam'].push({"teamId":"4","status":"pending"});
jsonStr = JSON.stringify(obj);
// "{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"},{"teamId":"4","status":"pending"}]}"

Answer 2

var Str_txt = '{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}';

如果要在最后位置添加，请使用代码

var parse_obj = JSON.parse(Str_txt);
parse_obj['theTeam'].push({"teamId":"4","status":"pending"});
Str_txt = JSON.stringify(parse_obj);
Output //"{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"},{"teamId":"4","status":"pending"}]}"

并且，如果要在第一个位置添加，则使用代码

var parse_obj = JSON.parse(Str_txt);
parse_obj['theTeam'].unshift({"teamId":"4","status":"pending"});
Str_txt = JSON.stringify(parse_obj);
Output //"{"theTeam":[{"teamId":"4","status":"pending"},{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}"

并且，任何人都想在数组的某个位置添加然后尝试下面的代码

fruits['theTeam'].splice(2, 0, {"teamId":"4","status":"pending"});
Output //"{"theTeam":[{"teamId":"1","status":"pending"},{"teamId":"2","status":"member"},{"teamId":"4","status":"pending"},{"teamId":"3","status":"member"}]}"

上面的代码块在第二个元素后添加一个元素。

Answer 3

首先，我们需要解析JSON对象，然后我们可以添加一个项目。

var str = '{"theTeam":[{"teamId":"1","status":"pending"},
{"teamId":"2","status":"member"},{"teamId":"3","status":"member"}]}';

var obj = JSON.parse(str);
obj['theTeam'].push({"teamId":"4","status":"pending"});
str = JSON.stringify(obj);

最后我们将obj JSON.stringify回json

Answer 4

例如，这里有一个元素，比如用于将项目添加到购物篮的按钮以及用于保存在localStorage中的相应属性。

'<a href="#" cartBtn pr_id='+e.id+' pr_name_en="'+e.nameEn+'" pr_price="'+e.price+'" pr_image="'+e.image+'" class="btn btn-primary"><i class="fa fa-shopping-cart"></i>Add to cart</a>'

---

var productArray=[];


$(document).on('click','[cartBtn]',function(e){
  e.preventDefault();
  $(this).html('<i class="fa fa-check"></i>Added to cart');
  console.log('Item added ');
  var productJSON={"id":$(this).attr('pr_id'), "nameEn":$(this).attr('pr_name_en'), "price":$(this).attr('pr_price'), "image":$(this).attr('pr_image')};


  if(localStorage.getObj('product')!==null){
    productArray=localStorage.getObj('product');
    productArray.push(productJSON);  
    localStorage.setObj('product', productArray);  
  }
  else{
    productArray.push(productJSON);  
    localStorage.setObj('product', productArray);  
  }


});

Storage.prototype.setObj = function(key, value) {
    this.setItem(key, JSON.stringify(value));
}

Storage.prototype.getObj = function(key) {
    var value = this.getItem(key);
    return value && JSON.parse(value);
}

将JSON对象添加到Array结果后（在LocalStorage中）：

[{“id”：“99”，“nameEn”：“Product Name1”，“price”：“767”，“image”：“1462012597217.jpeg”}，{“id”：“93”，“nameEn” ：“Product Name2”，“price”：“76”，“image”：“1461449637106.jpeg”}，{“id”：“94”，“nameEn”：“Product Name3”，“price”：“87” ， “图像”： “1461449679506.jpeg”}]

在此操作之后，您可以轻松地将数据作为List中的Java发送到服务器

完整的代码示例在这里

How do I store a simple cart using localStorage?