有没有办法在JavaScript中为数组的每个对象添加相同的项目val ="4"？

Question

有没有办法在JavaScript中为数组的每个对象添加相同的项目val ="4"？

让我们说有

var arr = [{"num":"111"},{"ttt":"123","rss":"456"},...];

我想得到

arr2 = [{"num":"111", "val":"4"},{"ttt":"123", "rss":"456", "val":"4"},...];

是否可以在一行中使用.push()数组或类似的东西？

Answer 1

该.map功能将为您创造奇迹!

var arr2 = arr.map(function(item) {
    item.val = 4;
    return item;
});

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map