c# - Asp.net MVC Razor如何显示两个模型字段的分组单选按钮

Question

我有一个简单的测验模型，我试图让用户从强类型 View 中分组的两个单选按钮中选择正确答案/替代答案。但我使用的 lambda 表达式不起作用。我得到两个空白的单选按钮。我在这里和网上查看了几个问题，但我的模型是 IList<>，并且我找不到合适的示例。我发现的所有示例都适用于非 IList<>。

这是我的模型

型号:

public partial class Question
    {
        public int QuestionID { get; set; }
        public string QuestionBody { get; set; }
        public string CorrectAnswer { get; set; }
        public string AlternativeAnswer { get; set; }           
    }

我的 Controller

public ActionResult Index()
        {
            QuizSimpleEntities quizEntities = new QuizSimpleEntities();
            var questions = from p in quizEntities.Questions
                            select p;

            return View(questions.ToList());

        }

我的模型:

  @model IList<Quiz.Models.Question>                                

 <h2>Welcome to the Quiz</h2>
  @Html.BeginForm(method:FormMethod.Post,controllerName:"Home",actionName:"index")
    {
        @foreach (var questions in Model)
        {

        <p>@questions.QuestionBody</p>  

        @* How to display the CorrectAnswer and AlternativeAnswer
           as two radio buttons grouped here? I will be posting the selected value back
        }

}

谢谢

Answer 1

您的 View 模型上需要有一个属性，用于在发布表单时保存所选答案:

public partial class Question
{
    public int QuestionID { get; set; }
    public string QuestionBody { get; set; }
    public string CorrectAnswer { get; set; }
    public string AlternativeAnswer { get; set; }           

    public string SelectedAnswer { get; set; }
}

然后简单地循环模型的元素并生成所需的标记:

@model IList<Quiz.Models.Question>                                

<h2>Welcome to the Quiz</h2>
@Html.BeginForm( method:FormMethod.Post, controllerName:"Home", actionName:"index")
{
    @for (var i = 0; i < Model.Count; i++)
    {
        @Html.HiddenFor(x => x[i].QuestionID)
        <fieldset>
            <legend>
                @Html.DisplayFor(x => x[i].QuestionBody)
            </legend>
            <ul>
                <li>
                    @Html.HiddenFor(x => x[i].CorrectAnswer)
                    @Html.RadioButtonFor(x => x[i].SelectedAnswer, Model[i].CorrectAnswer)
                    @Html.DisplayFor(x => x[i].CorrectAnswer)
                </li>
                <li>
                    @Html.HiddenFor(x => x[i].AlternativeAnswer)
                    @Html.RadioButtonFor(x => x[i].SelectedAnswer, Model[i].AlternativeAnswer)
                    @Html.DisplayFor(x => x[i].AlternativeAnswer)
                </li>
            </ul>
        </fieldset>
    }

    <button type="submit">OK</button>
}

注意:提交表单后，POST 操作可能会出现 IList<Question>您将在其中获得每个问题的答案的模型(在 SelectedAnswer 属性中)。