任务:使用for循环遍历数组，并向所有用户添加10个学分

Question

输出给我提示，在0位的人没有得到10个学分，但在输出中，我看到增加了10个学分(60)；

我有点糊涂。这个问题似乎很愚蠢，但我只需要重新评估一下。

​

var users = [
    {name: 'asdfasdf', credits: 50},
    {name: 'asasdfdf', credits: 10},
    {name: 'asdasdffasdf', credits: 11},
    {name: 'weewrwe', credits: 1},
    {name: 'werwer', credits: 190},
    {name: 'sdfsdf', credits: 100},
    {name: 'dfgdfg', credits: 0},
];

for(var i = 0; i < users.length; i++) {
  var obj = users[i];
}
console.log((obj.credits)+ 10);

​

Answer 1

您的var obj = users[i];将只为每个用户分配到obj，最后您将得到添加10的最后一个用户。

如果你这么做的话，你的脚本就能工作了

for(var i = 0; i < users.length; i++) { users[i].credits+=10; }

但这已经足够了，也更现代化了

users.forEach(user => user.credits += 10)

示例：

​

const users = [{name: 'asdfasdf', credits: 50},{name: 'asasdfdf', credits: 10},{name: 'asdasdffasdf', credits: 11},{name: 'weewrwe', credits: 1},{name: 'werwer', credits: 190},{name: 'sdfsdf', credits: 100},{name: 'dfgdfg', credits: 0}];

const amt = 10;
users.forEach(user => user.credits += amt)

console.log("Credits: ",users.map(user => user.credits).join(",")); // show just the credits

console.log(users); // show the users

​

Answer 2

​

var users = [
    {name: 'asdfasdf', credits: 50},
    {name: 'asasdfdf', credits: 10},
    {name: 'asdasdffasdf', credits: 11},
    {name: 'weewrwe', credits: 1},
    {name: 'werwer', credits: 190},
    {name: 'sdfsdf', credits: 100},
    {name: 'dfgdfg', credits: 0},
];

users.forEach(element => {
    if(element.credits != null) {
        element.credits = parseInt(element.credits) + 10;
    }
});

console.log(users);

​

Answer 3

试试这个：

 var len = users.length;
for(var i = 0; i <= len; i++){
    
    users[i].credits+=10;
}
console.log(users);