Question

有人可以告诉我在使用部分视图时如何让MVC绑定到视图模型中的视图模型？

 public class HomeController : Controller
    {
        //
        // GET: /Home/

        [HttpGet]
        public ActionResult Index()
        {
            AVm a = new AVm();
            BVm b = new BVm();
            a.BVm = b;

            return View(a);
        }

        [HttpPost]
        public ActionResult Index(AVm vm)
        {
            string name = vm.BVm.Name; // will crash BVm == null


            return View(vm);
        }
    }

//索引视图

@model MvcApplication4.Models.AVm

@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>

@using (Html.BeginForm("Index","Home",FormMethod.Post))
{
    <text>Id:</text> @Html.TextBoxFor(x => x.Id)
    @Html.Partial("SharedView", Model.BVm)

    <input type="submit" value="submit" />
}

// SharedView

@model MvcApplication4.Models.BVm

<text>Name:</text> @Html.TextBoxFor(x => x.Name)



 Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:


Line 26:         public ActionResult Index(AVm vm)
Line 27:         {
Line 28:             string name = vm.BVm.Name; // will crash BVm == null
Line 29: 
Line 30:

Answer 1

问题是，在您的部分模型BVm中，它不知道它是viewmodel AVm上的属性。因此，当您执行@Html.TextBoxFor(x => x.Name)之类的操作时，它只会生成类似

的内容

<input type="text" name="Name" id="Name" value="" />

当你真正需要的是

时

<input type="text" name="BVm.Name" id="Name" value="" />

你可以自己像这里建议的那样生成输入，或者你可以尝试类似的东西：

public ActionResult Index(AVm vm, BVm bvm)

假设没有冲突的属性名称。

为什么MVC在使用部分视图时不绑定？

1 个答案: