在对象数组中查找对象的索引

Question

我有这个

arr = [{name: 'pippo',lastname: 'p'},{name: 'mickey',lastname: 'mouse'}]

x ={name: 'mickey', lastname: 'mouse'}

arr.indexOf(x)

为什么 arr.indexOf(x) 返回 -1？是否有另一种解决方案可以在对象数组中查找对象的索引？

Answer 1

由于您有对象数组，因此无法直接使用indexOf()来获取该数组中该特定对象的索引。您需要使用findIndex()这样，当数组中有匹配的对象时，它会返回该对象的相应索引，否则-1。arr = [{name: 'pippo',lastname: 'p'},{name: 'mickey',lastname: 'mouse'}]x ={name: 'mickey', lastname: 'mouse'}console.log(arr.findIndex((obj) => obj.name == x.name && obj.lastname === x.lastname));

Answer 2

indexOf() 检查数组内对象的引用。由于您正在创建一个新对象并将其作为参数传递给 indexOf() 它与数组内对象的引用不匹配，因此它失败了。let arr = [{name: 'pippo',lastname: 'p'},{name: 'mickey',lastname: 'mouse'}]arr.indexOf(arr[1])而此代码将按预期返回 1，因为引用相同。@Ankit 给出的解决方案arr = [{name: 'pippo',lastname: 'p'},{name: 'mickey',lastname: 'mouse'}]x ={name: 'mickey', lastname: 'mouse'}console.log(arr.findIndex((obj) => obj.name == x.name && obj.lastname === x.lastname));

Answer 3

使用简单循环arr = [{name: 'pippo',lastname: 'p'},{name: 'mickey',lastname: 'mouse'}]x ={name: 'mickey', lastname: 'mouse'}for(let i=0;i< arr.length;i++){&nbsp; if(JSON.stringify(arr[i])===JSON.stringify(x))&nbsp; &nbsp;console.log(i)}