Create dynamic links in the navigation panel

Question

I am trying to dynamically create my top navigation panel in ASP.NET Core MVC 6.

I know it's simple but I cannot figure out how to make it work. Here is what I do (simplified):

My Model:

public class IP_Category

{

    public int id { get; set; }

    public string DisplayName { get; set; }

}

in my controller:

    public IActionResult Index()

    {

        //This way I dynamically pass data to my View

        ViewBag.Categories = _repository.ReturnCategories();

        return View();

    }

in my

cshtml

page:

@{

    //this info is in the top of the page, here I retrieve data passed from

    //controller and save it as a local variable

    var categories = (List<IP_Category>)ViewBag.Categories;

}

Then later in the _Layout where I take care of the navigation:

<ul class="nav navbar-nav">

    <li><a asp-controller="Home" asp-action="Index">Home</a></li>

    <li><a asp-controller="Home" asp-action="About">About</a></li>

    <li><a asp-controller="Home" asp-action="Contact">Contact</a></li>



    @foreach (var category in categories)

    {

        <li><a asp-controller="Home" asp-action="@category.DisplayName">@category.DisplayName</a></li>

    }

</ul>

The problem occurs with

asp-action="@category.DisplayName"

which does not generate appropriate href in my actual page.

So the question is what am I doing wrong? How can I pass

category.DisplayName

to my

asp-action

tag so the links work correctly?

Edit 1 - Adding more code:

Here is what was generated (note the missing href tag)

<ul class="nav navbar-nav">

    <li><a href="/">Home</a></li>

    <li><a href="/Home/About">About</a></li>

    <li><a href="/Home/Contact">Contact</a></li>



    <li><a href="">Item1</a></li>

    <li><a href="">Item2</a></li>

</ul>

Answer 1

if the controller and action don't match an existing controller and action then no href will be rendered. I suspect that @category.DisplayName does not match any actual action name on your home controller. Seems more likely that you have an action named Category that expects a parameter corresponding to the @category.DisplayName so it should be passed as a route parameter not as the action name

@foreach (var category in categories)
{
    <li><a asp-controller="Home" 
               asp-action="Category" 
       asp-route-category="@category.DisplayName">@category.DisplayName</a></li>
}

Create dynamic links in the navigation panel

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