$ .inArray不工作

Question

我遇到有关将对象存储到数组中的问题。但是当我尝试使用$ .inArray检查对象的存在时，它总是返回-1。我正在使用angularjs。

<input name="{{question.number}}"
            ng-click="radioSelected(question.choiceOneWeight, question.number,question.tmiGroup)"
            type="radio" value="{{question.choiceOneWeight}}" />



$scope.radioSelected = function(choice, question, tmiGroup) {
        var answer = {};
        answer.questionNumber = question;
        answer.answerWeight = choice;
        answer.tmiGroup = tmiGroup;

        if($.inArray(answer,userAnswers) < 0){
            userAnswers.push(answer);
        }
    };

我生成的答案对象是

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"}

如果我多次点击单选按钮，

userAnswers数组如下所示：

[{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},
{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},


{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"},

{"questionNumber":23,"answerWeight":1,"tmiGroup":"JP"}]

Answer 1

您不能使用 inArray() 来比较使用简单===

无法比较的任何内容

例如：

var a = [{x: 1}];
$.inArray({x: 1}, a); // => -1

在您的情况下，您可以在数组中存储每个问题的JSON字符串版本，然后在其上使用.inArray()。

即

var answer = JSON.stringify({
    questionNumber: question,
    answerWeight: choice,
    tmiGroup: tmiGroup
});

// now you can use inArray as 'answer' is nothing but a string (JSON)
if($.inArray(answer, userAnswers) < 0){
    userAnswers.push(answer);
}

从JSON.parse()

中检索问题时，请务必执行userAnswers

Answer 2

在javascript中，如果对象都引用相同的对象，则它们只被视为彼此相等。在您的情况下，虽然answer可能具有与数组中的对象完全相同的属性和值，但它是一个不同的对象，因此被认为不相等。

您需要将确切的对象传递给函数：

$scope.radioSelected = function(answer) {
    if($.inArray(answer,userAnswers) < 0){
        userAnswers.push(answer);
    }
});

然后

ng-click="radioSelected(question)"