常规推送和 Array.prototype.push.apply 有什么区别 [英] What's the difference between a regular push and an Array.prototype.push.apply

问题描述

我不太明白下面两行代码的区别.在我的代码中，带有apply"的那一行按照我想要的方式工作，而带有常规推送的那一行则不然.

I don't quite understand the difference between the following two lines of code. In my code, the line with "apply" works the way I want it to, and the line with just regular push doesn't.

那么当这两个都被执行时到底发生了什么:

So what is really going on when both of these are executed:

//this one does not work the way i want it to
$scope.items.push(result.data.stuff)

//this one works!
Array.prototype.push.apply($scope.items, result.data.stuff);

抱歉混淆，我修复了它，以便在那里有推送"方法

sorry for confusion, I fixed it so that it has the "push" method in there

推荐答案

New 1. 将数组推送到项目上.

New 1. That pushes the array onto items.

$scope.items = [1, 2];
result.data.stuff = [3, 4];
$scope.items.push(result.data.stuff);
$scope.items[0] === 1;
$scope.items[1] === 2;
$scope.items[2][0] === 3;
$scope.items[2][1] === 4;

旧的 1. 删除 $scope.items 中的现有引用.

Old 1. Drops the existing reference that was in $scope.items.

$scope.items = [1, 2];
result.data.stuff = [3, 4];
$scope.items = result.data.stuff;
$scope.items[0] === 3;
$scope.items[1] === 4;

2.将 result.data.stuff 中的所有项目推送到 $scope.items 中，保留现有项目.

2. Pushes all the items from result.data.stuff into $scope.items, keeping the existing items.

$scope.items = [1, 2];
result.data.stuff = [3, 4];
Array.prototype.push.apply($scope.items, result.data.stuff);
$scope.items[0] === 1;
$scope.items[1] === 2;
$scope.items[2] === 3;
$scope.items[3] === 4;

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