对MVC控制器方法的AJAX请求有500个错误

Question

如何将视图返回给AJAX调用？现在我用我的控制器方法用AJAX jQuery做一个get请求，但它命中了error处理程序。

我在视图中有这个下拉列表：

<select id="linkDocumentDropDown">
    <option value="ten">10</option>
    <option value="twentyfive">25</option>
    <option value="all">all result</option>
</select>

这个AJAX调用我的控制器返回视图：

$.ajax({
    url: "/Home/SearchResult",
    type: "GET", 
    data: { 
        searchString: $("#SearchString").val(), 
        pageSize: 25 
    },
    complete: function (xData, status) {
        $("#test").html(xData);
    },
    error: function (status) {
        alert(status.message);
    }
})

我的控制员：

public async Task<ActionResult> SearchResult(string searchString, int pageSize)
{
    QuestionAnswerService service = new QuestionAnswerService();
    SearchedQuestionsResponse searchResults = new SearchedQuestionsResponse();
    bool isSufficientLength = false;
    string[] searchTerms = searchString.Split(' ');
    foreach (string term in searchTerms)
    {
        if (term.Trim().Length > 2)
        {
            isSufficientLength = true;
            break;
        }
    }

    if (!string.IsNullOrEmpty(searchString) && isSufficientLength)
    {
        searchResults = await service.GetSearchQuestions(HttpContext.User.Identity.Name, searchString);
        Session["SearchResults"] = searchResults;

        if (searchResults.searchedquestions == null || searchResults.searchedquestions.Count == 0)
        {
            ViewBag.message = Messages.NoResults;
        }
        else
        {
            ViewBag.searchtext = Messages.SearchResults + " " + searchString;
            Session["SearchText"] = Messages.SearchResults + " " + searchString;
        }
    }
    else
    {
        ViewBag.message = Messages.SearchStringInvalid;
    }

    //  int pageSize = PAGE_SIZE;
    int pageNumber = PAGE_INDEX;

    return View(searchResults.searchedquestions.ToPagedList(pageNumber, pageSize));
}