Are you meaning a strongly-typed model; not custom? If you want to access fields'n properties of a document type you just need to use strongly typed models.

From your example, this would be making the 'item' as the 'MainNavLinkItem' type.

Something like:

foreach (var item in nav)
{
  // 'MainNavLinkItem' = whatever the name of your docType model is
  // 'navLinkItem' is just a variable to output if it's a successful cast; name however you like
  if (item is not MainNavLinkItem navLinkItem)
  {
    continue;
  }

  // then you can use 'navLinkItem' as a strongly typed variable and access all of that model's properties
}

This should also work for any custom extended properties you've made to your docType models.

I have class below, I want to convert or parse the MenuLinks alias to my class model.

public class MainNavigationLinkItemModel : BaseNodeViewModel
 {
     public Link Link { get; set; }

     public string Title { get; set; }

     public IList<MainNavigationSubMenuModel> SubMenus { get; set; } = new List<MainNavigationSubMenuModel>();

     public string FlyOutCaption { get; set; }

     public string FlyoutTitle { get; set; }

     public string FlyOutDescription { get; set; }

     public Link FlyOutButton { get; set; }

 }

By the way I am using umbraco 13. Is there any way or method that I can use? I don't want to parse it manually.

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