Inserting html tags between C# block code in cshtml file

Question

I want to use html tags between C# block code, I've tried it but I got errors. How can I insert html tags between C# block code in cshtml file?

The error is:

only assignment call increment decrement and new object expressions can be used as a statement

only assignment call increment decrement await and new object expressions can be used as a statement

@{
    Func<List<Comment>, Comment, HelperResult> ShowTree = null;
    ShowTree = (items, node) =>
    {
        @<text>
            <ul>
                @foreach (var comment in items)
                {

                }
            </ul>
         </text>;
        return null;
    };

}

Update:When I move the text outside the {}, I encountered some errors, too. Look at this picture.

Update 2: I've used @: but still there is a problem. that is ;expected

How can I solve this problem?

@{
Func<List<Comment>, Comment, int, HelperResult> ShowTree = null;
ShowTree = (items, parentItem, parentId) =>
{
    var count = items.Count(p => p.ParentId == parentId);
    if (count > 0)
    {
        @:<ul>
            foreach (var item in items.Where(p => p.ParentId == 
 parentId).ToList())
            {
            @:<li>
                string collapseId = string.Format("collapse_{0}", item.Id);
                @:<a class="btn btn-link" data-toggle="collapse" 
 href="#@{collapseId}" aria-expanded="True" aria-controls="@{collapseId}">
                    @:<span class="fa fa-minus" aria-hidden="true"> 
 Commenter Name</span>
                @:</a>
                    @:<div class="collapse show" id="@{collapseId}">
                        @:<div class="card">
                                @:<p>item.Description</p>
                        @:</div>
                            ShowTree(items, item, item.Id);
                    @:</div>
            @:</li>
            }
        @:</ul>
    }
    return null;
  };
};

Update 3: Latest codes with error messages in browser

@using Jahan.Beta.Web.App.Helper
@using Jahan.Beta.Web.App.Models
@using Microsoft.AspNetCore.Mvc.Razor
@using Jahan.Beta.Web.App.Helper
@model List<Comment>

@{
   Func<List<Comment>, Comment, int, HelperResult> ShowTree = null;
   ShowTree = (items, parentItem, parentId) =>
   {
   var count = items.Count(p => p.ParentId == parentId);
   if (count > 0)
   {
   @:<ul>
   @<text>@{
        foreach (var item in items.Where(p => p.ParentId ==    
   parentId).ToList())
        {
            string collapseId = string.Format("collapse_{0}", item.Id);
            <li>
                <a class="btn btn-link" data-toggle="collapse" href="@collapseId" aria-expanded="True" aria-controls="@collapseId">
                <span class="fa fa-minus" aria-hidden="true"> Commenter Name</span></a>
                <div class="collapse show" id="@collapseId"><div class="card"><p>@item.Description</p></div>
                    @ShowTree(items, item, item.Id);
                </div>
            </li>
        }
}</text>

@:</ul>
}
return null;
};
}


 @{
 Func<List<Comment>, HelperResult> CreateTree = null;
 CreateTree = commentList => new Func<List<Comment>, HelperResult>(
 @<text>@{
    List<Comment> nodesRoot = commentList.Where(p => p.ParentId == 
 null).ToList();
    <ul>
        @foreach (var comment in nodesRoot)
        {
            <li>
                <p>@comment.Description</p>
                @ShowTree(commentList, comment, comment.Id);
            </li>
        }
    </ul>
  }
   </text>)(null);
  }

<div class="media mb-4">
<div class="media-body">
    @CreateTree(Model)
</div>

</div>

An error occurred during the compilation of a resource required to process this request. Please review the following specific error details and modify your source code appropriately. Generated Code

; expected

Answer 1

For inline escape from C# codeblock in cshtml use @:. For example:

@{
    Func<List<Comment>, Comment, HelperResult> ShowTree = null;
    ShowTree = (items, node) =>
    {
        @:<ul>
            foreach (var comment in items)
                {

                }
        @:</ul>
        return null;
    };
}

Answer 2

As I see you want to render some content by mixing Html with C# code, instead of inserting your C# code in cshtml file you can create custom Html helper, it will be something like this:

     public static class CustomHtmlHelper
        {
            public static IHtmlContent ShowTree(this IHtmlHelper htmlHelper)
            {
                Func<List<Comment>, Comment, HelperResult> ShowTree = null;

                var builder = new StringBuilder();

                ShowTree = (items, node) =>
                {
                    builder.Append("<ul>");

                    foreach (var comment in items)
                    {
                        builder.Append("<li>"+comment.Content+"</li>");

                    }
                    builder.Append("</ul>");
                    return null;
                };

                //Just for testing purposes only

                var comments = new List<Comment> { new Comment { Content = "Comment 1" }, new Comment { Content = "Comment 2" } };

                ShowTree(comments, new Comment());

                //
                return new HtmlString(builder.ToString());

            }
        }

• In cshtml

  @Html.ShowTree()