我將模型切回了一個領域：//模型public class LetterViewModel{    public string LetterText;}//控制器public ActionResult Index(){    var model = new LetterViewModel();    model.LetterText = "Anything";    return View(model);}[HttpPost]public ActionResult Index(LetterViewModel model){     //model.LetterText == null    return View(model);}//視圖@model Test.Models.LetterViewModel@{    Layout = "~/Views/Shared/_Layout.cshtml";    ViewBag.Title = "Create a Letter";}@using (Html.BeginForm()){    <div id="Bottom">        @Html.TextAreaFor(m => m.LetterText)        <input type="submit" value="Ok" class="btn btn-default" />    </div>}當我在開發工具中檢查“網絡”選項卡時，它顯示輸入的值已包含在請求中。但是，當HttpPost控制器被激發時，該字段為空。