ASP.NET

var urlHelper = _urlHelperFactory.GetUrlHelper(_httpContextAccessor.HttpContext);

Argument 1: cannot convert from 'Microsoft.AspNetCore.Http.HttpContext' to 'Microsoft.AspNetCore.Mvc.ActionContext'

private static IActionContextAccessor _actionContextAccessor;
private static IUrlHelperFactory _urlHelperFactory;
public static void SetHttpContextAccessor(IActionContextAccessor accessor, IUrlHelperFactory urlHelperFactory) {
    _actionContextAccessor = accessor;
    _urlHelperFactory = urlHelperFactory;
}

var urlHelper = _urlHelperFactory.GetUrlHelper(_actionContextAccessor.ActionContext);

var accessor = serviceProvider.GetService<IActionContextAccessor>()
var userHelperFactory = serviceProvider.GetService<IUrlHelperFactory>()
HtmlHelperExt.SetHttpContextAccessor(accessor,userHelperFactory);

public static IHtmlContent CHGridTable<TModel>(this IHtmlHelper<TModel> htmlHelper, DataTable dt, object htmlAttributes = null)
{
    var urlHelperFactory = (IUrlHelperFactory)htmlHelper.ViewContext.HttpContext.RequestServices.GetService(typeof(IUrlHelperFactory));            
    var urlHelper = urlHelperFactory.GetUrlHelper(htmlHelper.ViewContext);
    string urlEdit = url.RouteUrl("Default");
    ...
}

Error CS0411 The type arguments for method 'HtmlHelperExt.CHGridTable<TModel>(HtmlHelper<TModel>, DataTable, object)' cannot be inferred from the usage. Try specifying the type arguments explicitly.

JimFeng wrote:

@HtmlHelperExt.CHGridTable(Model, new { tablename = "tblTest", defaultcolsort = "3" })

@Html.CHGridTable(Model, new { tablename = "tblTest", defaultcolsort = "3" })

@addTagHelper *, YourAssemblyNameHere

JimFeng wrote:

IHtmlHelper<dataset>' does not contain a definition for 'CHDropdownMenu'

CHDropdownMenu<tmodel>(this HtmlHelper<tmodel> htmlHelper,

public static IHtmlContent CHDropdownMenu<TModel>(this IHtmlHelper<TModel> htmlHelper, ...

@using HtmlHelperExt