我是asp.net的新手 . 通过尝试解决问题我得到了这个错误:
System.InvalidOperationException未由用户代码处理HResult = -2146233079 Message = Templates只能用于字段访问,属性访问,单维数组索引或单参数自定义索引器表达式 . Source = System.Web.Mvc StackTrace:位于System.Web.Mvc.Hv.DisplayNameExtensions.DisplayNameForInternal的System.Web.Mvc.ModelMetadata.FromLambdaExpression [TParameter,TValue](Expression
1表达式,ViewDataDictionary
1 viewData,ModelMetadataProvider metadataProvider) ASP中的System.Web.Mvc.Html.DisplayNameExtensions.DisplayNameFor [TModel,TValue](HtmlHelper1 html,Expression
1表达式)中的[TModel,TValue](HtmlHelper1 html,Expression
1表达式,ModelMetadataProvider metadataProvider) . _Page_Views_Users_Index_cshtml.Execute()位于c:\ Index.cshtml:第28行,位于System.Web.WebPages.Web上的System.Web.Mvc.WebViewPage.ExecutePageHierarchy()中的System.Web.WebPages.WebPageBase.ExecutePageHierarchy(),位于System.Web.WebPages.StartPage.RunPage( )System.Web.Mvc.RazorView.RenderView(ViewContext viewContext,TextWriter writer,System.Web.WebPages.WebartBase.ExecutePageHierarchy(WebPageContext pageContext,TextWriter writer,WebPageRenderingBase startPage)中的System.Web.WebPages.StartPage.ExecutePageHierarchy()对象在System.Web.Mvc.View.Mvc.Buvid.Rerult上的System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext,TextWriter writer)处于System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext,ActionResult actionResult)的System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext,TextWriter writer)在System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList1过滤器,Int32 filterIndex,ResultExecutingContext preContext,ControllerContext controllerContext,ActionResult actionResult)在System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList
1过滤器,Int32 filterIndex,ResultExecutingContext preContext, ControllerContext controllerContext,ActionResult actionResult)InnerException:
主要想法,我想在我看来代表2个模块 . 所以我为这两个模块创建了单独的类
public class TimeReportViewMod
{
public IEnumerable<TimeReportingLib.User> Model1 { get; set; }
public IPagedList<TimeReportingLib.User> Model2 { get; set; }
}
这是我的控制器,我回到我的视图:
public ActionResult Index(string sortOrder, string currentFilter, string searchString, int? page)
{
ViewBag.CurrentSort = sortOrder;
ViewBag.NameSortParm = String.IsNullOrWhiteSpace(sortOrder) ? "login_desc" : "";
var users = from s in db.Users.Include(u => u.CustomerProject).Include(u => u.Service).Include(u => u.Customer) select s;
//var sortUsers = from s in db.Users select s;
if(searchString != null)
{
page = 1;
}
else
{
searchString = currentFilter;
}
ViewBag.CurrentFilter = searchString;
if (!String.IsNullOrEmpty(searchString))
{
users = users.Where(s => s.Login.Contains(searchString) || s.UserName.Contains(searchString));
}
switch (sortOrder)
{
case "login_desc":
users = users.OrderByDescending(s => s.Login);
break;
default:
users = users.OrderBy(s => s.Login);
break;
}
int pageSize = 3;
int pageNumber = (page ?? 1);
return View("Index",new TimeReportViewMod());
}
这里是我的视图,我想获取我的用户登录名的数据,但我有异常:(
@model TimeReportingWebApp.TimeReportViewMod
@using PagedList.Mvc;
<link href="~/Content/PagedList.css" rel="stylesheet" type="text/css" />
@{
ViewBag.Title = "Users";
}
<h2>Users</h2>
<p>
@Html.ActionLink("Create New", "Create")
</p>
@using (Html.BeginForm("Index", "Users", FormMethod.Get))
{
<p>
Find by name: @Html.TextBox("SearchString", ViewBag.CurrentFilter as string)
<input type="submit" class="btn btn-primary" value="Search" />
</p>
}
<table class="table">
<tr>
<th>
@Html.ActionLink(Html.DisplayNameFor(m => m.Model1.Select(x => x.Login)).ToHtmlString(), "Index")
</th>
</tr>
@foreach (var item in Model.Model1) {
<tr>
<td>
@Html.DisplayFor(modelItem => item.Login)
</td>
</tr>
</table>
Page @(Model.Model2.PageCount < Model.Model2.PageNumber ? 0 : Model.Model2.PageNumber) of @Model.Model2.PageCount
如何使用lambda表达式访问我的数据?如何通过使用具有两个模块的类来正确地访问这些数据?
1 回答
好吧,我弄清楚主要问题是什么 . 首先,我不需要在ActionLink中提供对象名称,因为我无处可用 . 所以只需给它一个简单的字符串就足够了:
之后,我发现我没有在我的控制器中创建我的类的实例:UsersController.cs . 所以我宣布:
现在我可以在我的视图中完全访问2个模块 .