PagedListRenderOptions : How can I add FunctionToTransformEachPageLink page-link class?

I need help for asp.net; When I add this class as below, my list defines html tags as strings.

 @Html.PagedListPager(Model, page =>
                               Url.Action("Index", new { page = page }),
                               new PagedListRenderOptions
                               {

                                   UlElementClasses = new string[] { "pagination pagination-xs pagination-gutter  pagination-warning" },
                                   LiElementClasses = new string[] { "page-item" },
                                   LinkToPreviousPageFormat = "Geri",
                                   LinkToNextPageFormat = "İleri",
                                   ClassToApplyToLastListItemInPager = "page-previus",
                                   ClassToApplyToFirstListItemInPager = "page-next",

                                   FunctionToTransformEachPageLink = (li, a) =>
                                   {
                                       a.AddCssClass("page-link");
                                       li.SetInnerText(a.ToString());
                                       return li;

                                   }

                               })

How can I fix it :

<a not working html tag => <a class="page-link"

<ul class="pagination pagination-xs pagination-gutter  pagination-warning">

<a class="page-link">1</a> <a class="page-link" href="/Device?page=2">2</a> <a class="page-link" href="/Device?page=2" rel="next">İleri</a>

I fixed : li.InnerHtml = a.ToString();

@Html.PagedListPager(Model, page =>
                           Url.Action("Index", new { page = page }),
                           new PagedListRenderOptions
                           {

                               UlElementClasses = new string[] { "pagination pagination-xs pagination-gutter  pagination-warning" },
                               LiElementClasses = new string[] { "page-item" },
                               LinkToPreviousPageFormat = "Geri",
                               LinkToNextPageFormat = "İleri",
                               ClassToApplyToLastListItemInPager = "page-previus",
                               ClassToApplyToFirstListItemInPager = "page-next",

                               FunctionToTransformEachPageLink = (li, a) =>
                               {
                                   a.AddCssClass("page-link");
                                   li.InnerHtml = a.ToString();
                                   return li;

                               }

                           })