[英]ASP.Net MVC Postback from View to Controller shows null values
我在將ViewModel發布回控制器時遇到問題,但是ViewModel沒有從View正確映射到Controller。
TopicId和Content應該包含值,但是在回發時,它們不能:
VS調試:
ViewModels:
public class PostViewModel
{
public int PostId { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public string Author { get; set; }
public DateTime DateOfTopic { get; set; }
}
public class ReplyViewModel
{
public int TopicId { get; set; }
public string Content { get; set; }
}
public class PostListAndReplyVM
{
public List<PostViewModel> PostViewModel { get; set; }
public ReplyViewModel ReplyViewModel { get; set; }
}
視圖:
@model centreforum.Models.PostListAndReplyVM
@using (Html.BeginForm()) {
@Html.AntiForgeryToken()
@Html.ValidationSummary(true)
<fieldset>
<legend>Post</legend>
@Html.HiddenFor(model => model.ReplyViewModel.TopicId)
<div class="editor-label">
@Html.LabelFor(model => model.ReplyViewModel.Content)
</div>
<div class="editor-field">
@Html.EditorFor(model => model.ReplyViewModel.Content)
@Html.ValidationMessageFor(model => model.ReplyViewModel.Content)
</div>
<p>
<input type="submit" value="Create" />
</p>
</fieldset>
}
生成的HTML:
<form action="/Post/List/7/" method="post"><input name="__RequestVerificationToken" type="hidden" value="xxxxxxxxxxxxx" /> <fieldset>
<legend>Post</legend>
<input data-val="true" data-val-number="The field TopicId must be a number." data-val-required="The TopicId field is required." id="ReplyViewModel_TopicId" name="ReplyViewModel.TopicId" type="hidden" value="7" />
<div class="editor-label">
<label for="ReplyViewModel_Content">Content</label>
</div>
<div class="editor-field">
<input class="text-box single-line" id="ReplyViewModel_Content" name="ReplyViewModel.Content" type="text" value="" />
<span class="field-validation-valid" data-valmsg-for="ReplyViewModel.Content" data-valmsg-replace="true"></span>
</div>
<p>
<input type="submit" value="Create" />
</p>
</fieldset>
</form>
從生成的HTML中可以看到,TopicId肯定有一個值: value="7"
誰能看到問題出在表單發布和期望ReplyViewModel的控制器之間?
謝謝,
標記
輸入字段名稱以ReplyViewModel
為前綴(由於model => model.ReplyViewModel.*
lambda),因此您需要向模型綁定程序指示此信息:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult List([Bind(Prefix = "ReplyViewModel")] ReplyViewModel model)
{
...
}
或者,讓您的List操作采用PostListAndReplyVM模型:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult List(PostListAndReplyVM model)
{
// obviously only model.ReplyViewModel will be bound here because
// those are the only input fields in your form
...
}
問題在於您的視圖鍵入了PostListAndReplyVM
因此它創建了諸如ReplyViewModel.Content
名稱-但是,因為您的控制器操作需要一個ReplyViewModel
,所以無法綁定這些字段(即,沒有諸如ReplyViewModel.ReplyViewModel.Content
類的東西ReplyViewModel.ReplyViewModel.Content
)。
更改您的控制器操作:
public ActionResult List(PostListAndReplyVM reply)
或者,如果這是您的整個視圖,則只需將其鍵入ReplyViewModel
(並相應地更新HtmlHelper表達式)。
它為null,因為您將其綁定到另一個模型
視野中
@model centreforum.Models.PostListAndReplyVM
在行動中ReplyViewModel
嘗試像
public ActionResult SomeAction(PostListAndReplyVM model)
{
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.