更新对象数组而不会发生突变 [英] Updating an array of objects without mutation

问题描述

如果我有一个对象：

[
   {
       "value":"d1",
       "label":"bathstore.com",
       "selected":true
   },                             
   {
       "value":"d2",
       "label":"superdrug.com",
       "selected":true
   },
   {
       "value":"d3",
       "label":"papajohns.com",
       "selected":true
   }
]

如何使用传播运算符或Object.assign（）将'selected'字段的每个值更改为'false'，以避免对象突变？

how can I change every value of 'selected' field to 'false' using spread operator or Object.assign() to avoid object mutation?

推荐答案

您可以使用 map 遍历数组，并在每个回调内部使用传播语法创建具有更新属性的新对象：

You can iterate over array with map and inside each callback use spread syntax to create new objects with updated property:

let data = [
   {
       "value":"d1",
       "label":"bathstore.com",
       "selected":true
   },                             
   {
       "value":"d2",
       "label":"superdrug.com",
       "selected":true
   },
   {
       "value":"d3",
       "label":"papajohns.com",
       "selected":true
   }
];
 let newData = data.map((item) => {
    return {...item, selected: false};
 });
 console.log(newData);

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