EPiServer CMS 12 website UrlHelper.ContentUrl(contentreference) e

EPiServer CMS 12 website UrlHelper.ContentUrl(contentreference) error on reload of the page

Deepa Puranik

Vote:

Hello,

Below code works just fine to fetch siteasset or globalasset path on first load for the contentreference item passed as an argument.

public static string GetFriendlyLink(ContentReference contentReference)
{
var friendlyUrl = string.Empty;
if (contentReference != null)
{
var urlHelper = ServiceLocator.Current.GetInstance<IUrlHelper>();
friendlyUrl = urlHelper.ContentUrl(contentReference);
}

return friendlyUrl;
}

But on reload gives Value can't be Null exception for argument.

Value cannot be null. (Parameter 'provider')
at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService[T](IServiceProvider provider)

Adding UrlResolver works always. Can this be switched to UrlResolver instead of UrlHelper?

Please help on this.

Thanks,

Deepa

#296997

Feb 22, 2023 7:26

Quan Mai

Vote:

You should be using IUrlResolver. I don't even recognize IUrlHelper, it's not part of our public APIs

#296998

Feb 22, 2023 9:11

Karol Berezicki

Vote:

Hi Deepa,

If you take a look inside the method ContentUrl of UrlHelper, it uses the IUrlResolver internally.
I would advise to cut the middle man and use the IUrlResolver :)

    /// <summary>
    /// Resolves an URL using routing for a specific <see cref="T:EPiServer.Core.ContentReference" />
    /// </summary>
    /// <param name="urlHelper">The URL helper instance that this method extends</param>
    /// <param name="contentLink">The content reference to resolve</param>
    /// <returns>The URL or an empty string</returns>
    public static string ContentUrl(this IUrlHelper urlHelper, ContentReference contentLink)
    {
      UrlResolver requiredService = urlHelper.ActionContext.HttpContext.RequestServices.GetRequiredService<UrlResolver>();
      if (!ContentReference.IsNullOrEmpty(contentLink))
      {
        string url = requiredService.GetUrl(contentLink);
        if (!string.IsNullOrEmpty(url))
          return UrlEncoder.Encode(url);
      }
      return string.Empty;
    }

#296999

Feb 22, 2023 9:13

Deepa Puranik

Vote:

Thank you both for all the help.

#297000

Feb 22, 2023 9:29