Javascript:使用`.includes`查找对象数组是否包含特定对象 [英] Javascript: Using `.includes` to find if an array of objects contains a specific object

问题描述

我对javascript ES6有点陌生，并且我很难理解为什么以下内容无法按预期运行:

I am a bit new to javascript ES6, and I am having difficulty understanding why the below is not functioning as expected:

let check = [{name: 'trent'},{name: 'jason'}].includes({name: 'trent'}); 
// expect true - returns false

谢谢！

推荐答案

includes本质上检查是否有元素===您要搜索的元素.对于对象，===的含义实际上是相同的对象，与相同的引用(在内存中的相同位置)相同，而不是相同的形状.

includes essentially checks if any element === the element you're searching for. In case of objects, === means literally the same object, as in the same reference (same place in memory), not the same shape.

var a1 = { name: 'a' }
var a2 = { name: 'a' }

console.log(a1 === a2) // false because they are not the same object in memory even if they have the same data

但是，如果您搜索实际上在数组中的对象，那么它将起作用:

But if you search for an object that is actually in the array it works:

var a1 = { name: 'a' }
var a2 = { name: 'a' }
var array = [a1, a2]

console.log(array.includes(a1)) // true because the object pointed to by a1 is included in this array 

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