C# 无法在帖子中输出所有评论
我想在一篇博客文章中输出所有评论。我已经成功地在数据库中输入了所有数据,我可以输出帖子。但是,我无法输出评论 我的帖子模式如下:C# 无法在帖子中输出所有评论,c#,asp.net-mvc,entity,C#,Asp.net Mvc,Entity,我想在一篇博客文章中输出所有评论。我已经成功地在数据库中输入了所有数据,我可以输出帖子。但是,我无法输出评论 我的帖子模式如下: public class Post { [Key] public int PostId { get; set; } public string Title { get; set; } public DateTime CreatedDate{get;set;} public Da
public class Post
{
[Key]
public int PostId { get; set; }
public string Title { get; set; }
public DateTime CreatedDate{get;set;}
public DateTime UpdateDate { get; set; }
public string Body { get; set; }
public ICollection<Comment> Comments { get; set;}
}
public int CommentId { get; set; }
public int PostId { get; set; }
[ForeignKey("PostId")]
public virtual Post Post{get; set;}
public string CommentCreateDate { get; set; }
public string CommentUpdateDate { get; set; }
public string CommeterName { get; set; }
public string EmailAddress { get; set; }
public string CommentText { get; set; }
public bool Approved { get; set; }
[HttpPost]
public ActionResult CreateComment(int ?id, CommentViewModel model)
{
Post post = GetPost(id);
var comment = new Comment();
comment.Post = post;
comment.CommentCreateDate = DateTime.Now.ToString();
comment.CommeterName = model.Name;
comment.EmailAddress = model.Email;
comment.CommentText = model.Text;
db.Comments.Add(comment);
db.SaveChanges();
m_commentList.Add(m_comment);
ViewData["Comment"] = comment;
ViewBag.Comment = comment;
TempData["Comment"] = comment;
return RedirectToAction("Index");
}
@using Blog.Models
@{
ViewBag.Title = "Index";
var viewDataComment = ViewData["Comment"] as Comment;
var tempDataComment = TempData["Comment"] as Comment;
bool isPreviousLinkVisible = ViewBag.IsPreviousLinkVisible ?? false;
bool isNextLinkVisible = ViewBag.IsNextLinkVisible ?? false;
bool isAdmin = ViewBag.IsAdmin ?? false;
}
@foreach (Post post in Model)
{
<div class="newsResult">
<div class="title">@Html.DisplayFor(modelItem => post.Title)</div>
<div class="updated"> <b>Created:</b> @Html.DisplayFor(modelItem => post.CreatedDate) </div>
<div class="updated"> <b>Updated:</b> @Html.DisplayFor(modelItem => post.UpdateDate)</div>
<div class="data"> <b></b> @Html.DisplayFor(modelItem => post.Body)</div>
@*<div class="data"> <b></b> @Html.DisplayFor(x => tempDataComment.CommentText)</div>*@
@foreach (Comment comment in post.Comments.OrderBy(x => x.CommentCreateDate)) //Offending line
{
<div class="comment">
<div class="commentName">
@if (!string.IsNullOrWhiteSpace(comment.EmailAddress))
{
<a href="mailto: @comment.EmailAddress;">@comment.CommeterName</a>
}
else
{
@comment.CommeterName;
}
</div>
said:
<div class="commentBody">@Html.Raw(Html.Encode(comment.CommentText).Replace("\n", "<br/>"))</div>
<div class="commentTime">at @comment.CommentCreateDate.ToString() on @comment.CommentCreateDate.ToString()</div>
</div>
}
我的行动如下:
public class Post
{
[Key]
public int PostId { get; set; }
public string Title { get; set; }
public DateTime CreatedDate{get;set;}
public DateTime UpdateDate { get; set; }
public string Body { get; set; }
public ICollection<Comment> Comments { get; set;}
}
public int CommentId { get; set; }
public int PostId { get; set; }
[ForeignKey("PostId")]
public virtual Post Post{get; set;}
public string CommentCreateDate { get; set; }
public string CommentUpdateDate { get; set; }
public string CommeterName { get; set; }
public string EmailAddress { get; set; }
public string CommentText { get; set; }
public bool Approved { get; set; }
[HttpPost]
public ActionResult CreateComment(int ?id, CommentViewModel model)
{
Post post = GetPost(id);
var comment = new Comment();
comment.Post = post;
comment.CommentCreateDate = DateTime.Now.ToString();
comment.CommeterName = model.Name;
comment.EmailAddress = model.Email;
comment.CommentText = model.Text;
db.Comments.Add(comment);
db.SaveChanges();
m_commentList.Add(m_comment);
ViewData["Comment"] = comment;
ViewBag.Comment = comment;
TempData["Comment"] = comment;
return RedirectToAction("Index");
}
@using Blog.Models
@{
ViewBag.Title = "Index";
var viewDataComment = ViewData["Comment"] as Comment;
var tempDataComment = TempData["Comment"] as Comment;
bool isPreviousLinkVisible = ViewBag.IsPreviousLinkVisible ?? false;
bool isNextLinkVisible = ViewBag.IsNextLinkVisible ?? false;
bool isAdmin = ViewBag.IsAdmin ?? false;
}
@foreach (Post post in Model)
{
<div class="newsResult">
<div class="title">@Html.DisplayFor(modelItem => post.Title)</div>
<div class="updated"> <b>Created:</b> @Html.DisplayFor(modelItem => post.CreatedDate) </div>
<div class="updated"> <b>Updated:</b> @Html.DisplayFor(modelItem => post.UpdateDate)</div>
<div class="data"> <b></b> @Html.DisplayFor(modelItem => post.Body)</div>
@*<div class="data"> <b></b> @Html.DisplayFor(x => tempDataComment.CommentText)</div>*@
@foreach (Comment comment in post.Comments.OrderBy(x => x.CommentCreateDate)) //Offending line
{
<div class="comment">
<div class="commentName">
@if (!string.IsNullOrWhiteSpace(comment.EmailAddress))
{
<a href="mailto: @comment.EmailAddress;">@comment.CommeterName</a>
}
else
{
@comment.CommeterName;
}
</div>
said:
<div class="commentBody">@Html.Raw(Html.Encode(comment.CommentText).Replace("\n", "<br/>"))</div>
<div class="commentTime">at @comment.CommentCreateDate.ToString() on @comment.CommentCreateDate.ToString()</div>
</div>
}
我的索引视图如下:
public class Post
{
[Key]
public int PostId { get; set; }
public string Title { get; set; }
public DateTime CreatedDate{get;set;}
public DateTime UpdateDate { get; set; }
public string Body { get; set; }
public ICollection<Comment> Comments { get; set;}
}
public int CommentId { get; set; }
public int PostId { get; set; }
[ForeignKey("PostId")]
public virtual Post Post{get; set;}
public string CommentCreateDate { get; set; }
public string CommentUpdateDate { get; set; }
public string CommeterName { get; set; }
public string EmailAddress { get; set; }
public string CommentText { get; set; }
public bool Approved { get; set; }
[HttpPost]
public ActionResult CreateComment(int ?id, CommentViewModel model)
{
Post post = GetPost(id);
var comment = new Comment();
comment.Post = post;
comment.CommentCreateDate = DateTime.Now.ToString();
comment.CommeterName = model.Name;
comment.EmailAddress = model.Email;
comment.CommentText = model.Text;
db.Comments.Add(comment);
db.SaveChanges();
m_commentList.Add(m_comment);
ViewData["Comment"] = comment;
ViewBag.Comment = comment;
TempData["Comment"] = comment;
return RedirectToAction("Index");
}
@using Blog.Models
@{
ViewBag.Title = "Index";
var viewDataComment = ViewData["Comment"] as Comment;
var tempDataComment = TempData["Comment"] as Comment;
bool isPreviousLinkVisible = ViewBag.IsPreviousLinkVisible ?? false;
bool isNextLinkVisible = ViewBag.IsNextLinkVisible ?? false;
bool isAdmin = ViewBag.IsAdmin ?? false;
}
@foreach (Post post in Model)
{
<div class="newsResult">
<div class="title">@Html.DisplayFor(modelItem => post.Title)</div>
<div class="updated"> <b>Created:</b> @Html.DisplayFor(modelItem => post.CreatedDate) </div>
<div class="updated"> <b>Updated:</b> @Html.DisplayFor(modelItem => post.UpdateDate)</div>
<div class="data"> <b></b> @Html.DisplayFor(modelItem => post.Body)</div>
@*<div class="data"> <b></b> @Html.DisplayFor(x => tempDataComment.CommentText)</div>*@
@foreach (Comment comment in post.Comments.OrderBy(x => x.CommentCreateDate)) //Offending line
{
<div class="comment">
<div class="commentName">
@if (!string.IsNullOrWhiteSpace(comment.EmailAddress))
{
<a href="mailto: @comment.EmailAddress;">@comment.CommeterName</a>
}
else
{
@comment.CommeterName;
}
</div>
said:
<div class="commentBody">@Html.Raw(Html.Encode(comment.CommentText).Replace("\n", "<br/>"))</div>
<div class="commentTime">at @comment.CommentCreateDate.ToString() on @comment.CommentCreateDate.ToString()</div>
</div>
}
我确信数据已经创建,其中包括在vartempDataComment
中可用的注释
为什么会这样?有人能帮忙吗
提前谢谢你 通过添加空值检查修复了该问题:
@if (post.Comments != null) //added this
{
foreach (Comment comment in post.Comments.OrderBy(x => x.CommentCreateDate))
{
<div class="comment">
<div class="commentName">
@if (!string.IsNullOrWhiteSpace(comment.EmailAddress))
{
<a href="mailto: @comment.EmailAddress;">@comment.CommeterName</a>
}
else
{
@comment.CommeterName;
}
</div>
said:
<div class="commentBody">@Html.Raw(Html.Encode(comment.CommentText).Replace("\n", "<br/>"))</div>
<div class="commentTime">at @comment.CommentCreateDate.ToString() on @comment.CommentCreateDate.ToString()</div>
</div>
}
}
@if(post.Comments!=null)//添加了这个
{
foreach(post.Comments.OrderBy(x=>x.CommentCreateDate)中的注释)
{
@如果(!string.IsNullOrWhiteSpace(comment.EmailAddress))
{
}
其他的
{
@CommeterName;
}
说:
@Html.Raw(Html.Encode(comment.CommentText).Replace(“\n”,“
”))
在@comment.CommentCreateDate.ToString()上的@comment.CommentCreateDate.ToString()处
}
}
这是在post还是get中发生的??你的帖子刚刚回到索引?这是在帖子中发生的。在post控制器的索引视图中,即上面的视图。我想列出该视图中的所有注释。检查您传递给控制器的模型是否有值。我想它是来的NULL@Peru但是我传递给后置控制器的模型,也就是CommentView模型,不是空的,它已经在数据库中输入了数据,然后它在var tempDataComment中可用。。。