小编kda*_*eid的帖子

从ASP.NET Core RC1迁移到RC2时,我的TagHelper无法解析注入的IUrlHelpers.

[HtmlTargetElement("usermenulink", Attributes = "controller-name, action-name, menu-text, menu-item, active-item")]

public class UserMenuItemTagHelper : TagHelper
{
    public IUrlHelper _UrlHelper { get; set; }

    public UserMenuItemTagHelper(IUrlHelper urlHelper)
    {
        _UrlHelper = urlHelper;
    }
    //... abbreviated
}

相反,我得到一个例外:

处理请求时发生未处理的异常.

  InvalidOperationException: Unable to resolve service for type 'Microsoft.AspNetCore.Mvc.IUrlHelper' while attempting to activate '...TagHelpers.UserMenuItemTagHelper'.

有任何想法吗？