.NET MVC中如何将Event ID从视图传递到分部视图再到控制器

我在.NET MVC Web应用中，需要将Event模型的ID从事件详情视图传递到用于评论该事件的分部视图（通过Ajax渲染），再传递到分部视图的Post控制器动作，为评论分配EventId以建立数据库关联。视图与分部视图使用不同模型，请问该如何实现？

工作流 #

• 视图（详情页，模型1：Event）→ 分部视图（创建评论，模型2：Comment）→ 控制器（CommentController的Create动作）
• Event.Id → 传递到分部视图 → 提交评论时，将ID发送到Create动作

详情视图代码（修改后） #

@using Evented.Domain.Models
@using Microsoft.AspNetCore.Identity
@model Evented.Web.EventVMCompany

@inject UserManager<User> UserManager
@{    
    ViewData["Title"] = "Detail";
}
<h1>Detail</h1>

<h4>EventVM</h4>
<hr />
@Html.ValidationMessageFor(m => m.Id)
<form asp-action="JoinEvent">
    <div>
        <dl class="row">
            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.Id)
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.Id)
                @Html.HiddenFor(model=>model.Id)

            </dd>
            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.Topic)
                @Html.HiddenFor(model=>model.Topic)
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.Topic)
            </dd>

            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.Title)
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.Title)
                @Html.HiddenFor(model=>model.Title)

            </dd>
            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.Description)
                @Html.HiddenFor(model=>model.Description)
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.Description)

            </dd>
            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.Location)
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.Location)
                @Html.HiddenFor(model=>model.Location)

            </dd>
            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.BeginsAt)
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.BeginsAt)
                @Html.HiddenFor(model=>model.BeginsAt)

            </dd>
            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.EndsAt)
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.EndsAt)
                @Html.HiddenFor(model=>model.EndsAt)

            </dd>
            <dt class="col-sm-2">
                @Html.DisplayNameFor(model => model.joineeLimit )
            </dt>
            <dd class="col-sm-10">
                @Html.DisplayFor(model => model.joineeLimit)
                @Html.HiddenFor(model=>model.joineeLimit)
            </dd>
            @Html.HiddenFor(model=>model.CreatorId)
            @Html.HiddenFor(model=>model.joineeNumber)
            @Html.HiddenFor(model=>model.UsersJoined)
            @Html.HiddenFor(model=>model.UsersJoined.Count)
        </dl>
    </div>
    @{
        if (Model.CreatorId != UserManager.GetUserId(User))
        {
            @foreach (var item in Model.UsersJoined)
            {
                @if (item.UserId != UserManager.GetUserId(User))
                {
                    <button type="submit" class="btn btn-primary">Join</button>
                }
                else
                {
                    <button type="submit" formaction="/Event/LeaveEvent" class="btn btn-primary">Leave</button>
                }
            }
            @if (Model.UsersJoined.Count == 0)
            {
                <button type="submit" class="btn btn-primary">Join</button>
            }
        }
    }
</form>
<a asp-action="Index" class="btn btn-primary">Back to List</a>


<div>@{    
    foreach (var item in Model.UsersJoined)
    {
        if (item.UserId == UserManager.GetUserId(User))
        {
                <div id="commentlist"></div>
        }
    }
}</div>
<div id="createcomment"></div>


<script type="text/javascript">
    // 直接传递当前事件的ID到评论分部视图
    $('#createcomment').load('@Url.Action("Create","Comment", new { eventId = Model.Id })');
    $('#commentlist').load('@Url.Action("Index","Comment", new { eventId = Model.Id })');
</script>

分部视图代码（修改后） #

@model Evented.Web.CommentVM
@{
    // 接收从路由传递过来的EventId
    int eventId = ViewBag.EventId ?? 0;
}

<hr />
<div class="row">
    <div class="col-md-4">
        <form asp-action="Create" method="post">
            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
            <!-- 添加隐藏字段，提交表单时自动传递EventId -->
            <input type="hidden" name="eventId" value="@eventId" />
        
            <div class="form-group">
                <input asp-for="Text" class="form-control" placeholder="Comment"/>
                <span asp-validation-for="Text" class="text-danger"></span>
            </div>
         
            <div class="form-group">
                <input name="button" id="button" type="submit" value="Comment" class="btn btn-primary " />
            </div>
        </form>
    </div>
</div>

控制器Create动作代码（修改后） #

[HttpPost]
[ValidateAntiForgeryToken]
public async Task<ActionResult> Create(CommentVM commentVM, int eventId)
{
    // 异步获取当前用户，避免同步阻塞
    User usr = await usrManager.GetUserAsync(User);

    var comment = mapper.Map<Comment>(commentVM);
    comment.EventId = eventId;
    comment.User = usr;
    comment.CreatedAt = DateTime.Now;
    comment.UpdatedAt = DateTime.Now;

    await commentService.AddCommentAsync(comment);
    // 跳转回对应事件的详情页或评论列表
    return RedirectToAction("Detail", "Event", new { id = eventId });
}

关键修改说明 #

1. 详情视图Ajax请求：
   原代码中ViewData["EventId"]未赋值，改为直接传递Model.Id作为路由参数，确保分部视图能获取到当前事件的ID。
2. 分部视图存储EventId：
   通过ViewBag.EventId接收路由参数，添加隐藏字段将EventId存入表单，提交时自动传递到控制器。
3. 控制器动作优化：
   将同步获取用户的方式改为异步调用，避免阻塞；跳转时携带EventId，确保回到对应事件的页面。

内容的提问来源于stack exchange，提问作者Furkan Koç