当我发回到控制器时，模型的所有值都为空

Question

我将模型切回了一个领域：//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);}//视图@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>}当我在开发工具中检查“网络”选项卡时，它显示输入的值已包含在请求中。但是，当HttpPost控制器被激发时，该字段为空。

Answer 1

您需要在参数之前添加[FromBody]到操作

[HttpPost]

public ActionResult Index([FromBody]LetterViewModel model)

{ 

    //model.LetterText == null

    return View(model);

}