Question

每当我运行此代码时，我都有问题从控制器传递结果以从httppost方法查看。服务器端代码很好，只是当我在calculator.Result属性中分配一个新结果时，我从未在视图的文本框中看到新分配的值。其余的属性都填充了适当的值。

有谁可以请帮助我如何解决这个问题？或者我错过了什么？

谢谢

这是我的代码来自.cshtml

    @using (Html.BeginForm())
    {
        @Html.ValidationSummary(true)
        <div class="row">
            <div class="span2">
                @Html.LabelFor(x => x.FirstNumber)
            </div>
            <div class="span2">
                @Html.TextBoxFor(x => x.FirstNumber)
            </div>
            <div class="field-validation-error">
                @Html.ValidationMessageFor(x => x.FirstNumber)
            </div>
        </div>
        <br />
        <div class="row">
            <div class="span2">
                @Html.LabelFor(x => x.SecondNumber)
            </div>
            <div class="span2">
                @Html.TextBoxFor(x => x.SecondNumber)
            </div>
            <div class="field-validation-error">
                @Html.ValidationMessageFor(x => x.SecondNumber)
            </div>
        </div>
        <br />
        <div class="row">
            <div class="span2">
                @Html.LabelFor(x => x.SelectedFunction)
            </div>
            <div class="span2">
                @Html.DropDownListFor(x => x.SelectedFunction, Model.Functions, "Please Make a Selection")
            </div>
            <div class="field-validation-error">
                @Html.ValidationMessageFor(x => x.SelectedFunction)
            </div>
        </div>
        <br/>
        <div class="row">
            <div class="span2">
                @Html.Label("Result: ")
            </div>
            <div class="span2">
                @Html.TextBoxFor(x => x.Result)
            </div>
        </div>
        <br />
        <div class="row">
            <input type="submit" value="Load" />
        </div>

    }

这是我在控制器后面的代码

  [HttpPost]
    public ActionResult Index(CalculatorViewModels calculator)
    {
        //If the entries are valid
        if (ModelState.IsValid)
        {

            try
            {
                double firstNum = calculator.FirstNumber;
                double secondNum = calculator.SecondNumber;
                string selectedFunction = calculator.SelectedFunction;

                double result = -1;
                if (selectedFunction.Equals("1"))
                {
                    result = service.CombinedWith(firstNum, secondNum);
                }
                else if (selectedFunction.Equals("2"))
                {
                    result = service.Either(firstNum, secondNum);
                }

               calculator.Result = Convert.ToString(result);

                return View(calculator);
            }
            catch(Exception ex)
            {
               calculator.Result = "Error in calculating probability "+ex.Message;
                return View(calculator);
            }
        }

        //entries are not valid 
        else
        {
            return View(calculator);
        }

    }

这是我的视图模型

公共类CalculatorViewModels {

    [Required(ErrorMessage = "Please enter a Number between zero and one")]
    [Display(Name = "FirstNumber")]
    [Range(0, 1)]
    public double FirstNumber { get; set; }

    [Required(ErrorMessage = "Please enter a Number between zero and one")]
    [Display(Name = "Second Number")]
    [Range(0, 1)]
    public double SecondNumber { get; set; }

    [Required(ErrorMessage = "Please Select at least one function")]
    [Display(Name="Please Select a Function")]
    public string SelectedFunction { get; set; }

    //will be used to report exception as well if needed 
    public string Result { get; set; }

    public List<SelectListItem> Functions
    {
        get
        {
            return new List<SelectListItem>()
            {
                new SelectListItem{ Text="CombinedWith",Value="0"},
                new SelectListItem{Text="Either",Value="1"}
            };

        }
    }


}

Answer 1

在视图的顶部，转储模型的内容仅用于进行健全性检查。使用HTML.Raw（..）或其他东西，然后查看页面源以检查结果是否实际设置。

像

这样的东西

@{
    var model = @Html.Raw(Json.Encode(Model));
}

使用JavaScript将模型写出到控制台或其他东西。

让我知道你是如何进行的，以及结果是否已经确定。

Answer 2

尝试这种方法......

1）更新视图，为提交按钮添加点击处理程序，并在javascript中处理

@using (Html.BeginForm())
    {
        @Html.ValidationSummary(true)
        <div class="row">
            <div class="span2">
                @Html.LabelFor(x => x.FirstNumber)
            </div>
            <div class="span2">
                @Html.TextBoxFor(x => x.FirstNumber)
            </div>
            <div class="field-validation-error">
                @Html.ValidationMessageFor(x => x.FirstNumber)
            </div>
        </div>
        <br />
        <div class="row">
            <div class="span2">
                @Html.LabelFor(x => x.SecondNumber)
            </div>
            <div class="span2">
                @Html.TextBoxFor(x => x.SecondNumber)
            </div>
            <div class="field-validation-error">
                @Html.ValidationMessageFor(x => x.SecondNumber)
            </div>
        </div>
        <br />
        <div class="row">
            <div class="span2">
                @Html.LabelFor(x => x.SelectedFunction)
            </div>
            <div class="span2">
                @Html.DropDownListFor(x => x.SelectedFunction, Model.Functions, "Please Make a Selection")
            </div>
            <div class="field-validation-error">
                @Html.ValidationMessageFor(x => x.SelectedFunction)
            </div>
        </div>
        <br/>
        <div class="row">
            <div class="span2">
                @Html.Label("Result: ")
            </div>
            <div class="span2">
                @Html.TextBoxFor(x => x.Result)
            </div>
        </div>
        <br />
        <div class="row">
            <input type="button" value="Load" id="btnSubmit" onclick="submitForm();"/>
        </div>

    }

<script src="~/Scripts/jquery-2.1.3.js"></script>
<script type="text/javascript">
    var url = '@Url.Action("Index")';

    function submitForm() {
        var data = {};
        data.FirstNumber = $('#FirstNumber').val();
        data.SecondNumber = $('#SecondNumber').val();
        data.SelectedFunction = $('#SelectedFunction').val();
        $.post(url, data).done(function (result) {
            $('#Result').val(result);
        });
    }


</script>

修改控制器以返回Json数据

using Newtonsoft.Json;
..
..

[HttpPost]
        public ActionResult Index(CalculatorViewModels calculator)
        {
            //If the entries are valid
            if (ModelState.IsValid)
            {

                try
                {
                    double firstNum = calculator.FirstNumber;
                    double secondNum = calculator.SecondNumber;
                    string selectedFunction = calculator.SelectedFunction;

                    double result = -1;
                    if (selectedFunction.Equals("1"))
                    {
                        result = service.CombinedWith(firstNum, secondNum);
                    }
                    else if (selectedFunction.Equals("2"))
                    {
                        result = service.Either(firstNum, secondNum);
                    }

                    calculator.Result = Convert.ToString(result);

                    return Json(result);
                }
                catch (Exception ex)
                {
                    calculator.Result = "Error in calculating probability " + ex.Message;
                    return Json(0);
                }
            }

            //entries are not valid 
            else
            {
                return Json(0);
            }

        }

不要忘记将jQuery库添加到scripts文件夹并添加对Newtonsoft.Json的引用。希望这会有所帮助。

当从httppost控制器传递到视图时，asp.mvc视图模型不会持久保存新分配的数据

2 个答案: