javascript - 如何使用 $localstorage 在 Angularjs 中添加投票系统

Question

I want to restrict user to vote only one time for a question using $localstorage.

这是我的代码:HTML:

<ul>
    <li ng-repat="question in questions"> {{question.text}} 
    <button ng-click="upvote(question)">Vote</button>
</li>

JS:

$scope.upvote = function(question){
  var votedQuestions = [];
$localStorage.votedQuestions = votedQuestions;
if($localStorage.votedQuestions.indexof(question._id) === -1){

$localStorage.votedQuestions.push(question._id);
 console.log("Thanks for Voting");
}
else {
 console.log("You already voted to this question");
}

}
}

它给了我错误，比如$localStorage.votedQuestions.indexof不是一个函数

并且它不存储多个问题，它只是在其他问题点击时更新本地存储数组中的问题 ID

Answer 1

您始终将 $localStorage.votedQuestions 设置为空数组，因此用户始终可以对所有问题进行投票。

只需删除此行即可正常工作

 //APP
angular.module('myApp')
    .run(['$localStorage', function($localStorage) {
        $localStorage.votedQuestions = [];
    }])

//Controller
$scope.upvote = function(question) {
    if ($localStorage.votedQuestions.indexof(question._id) === -1) {
        $localStorage.votedQuestions.push(question._id);
        console.log("Thanks for Voting");
    } else {
        console.log("You already voted to this question");
    }
}