对象引用未设置为布局页面上对象的实例

我在编辑页面中有一个编辑表单.当我第一次进入页面时一切正常.但是在提交表单后我看到了这个错误:

你调用的对象是空的.描述:执行当前Web请求期间发生未处理的异常.请查看堆栈跟踪以获取有关错误及其源自代码的位置的更多信息.

异常详细信息:System.NullReferenceException:未将对象引用设置为对象的实例.

在源错误中你看到了这个:

@{
    ViewBag.Title = "Edit";
    Layout ="~/Views/Shared/_Layout.cshtml";
}

现在有什么问题？!

更新

我的观看代码:

@model Portal.Web.CMS.Models.PageViewModel

@{
    ViewBag.Title = "?????? ????";
    Layout ="~/Views/Shared/_Layout.cshtml";
}

????

    
???? ????? /
    
@Model.Name /
    
?????? ????

@using (Html.BeginForm())
{
    @Html.ValidationSummary(true)

    @Html.HiddenFor(model => model.PageId)
    

        @Html.LabelFor(model => model.Lang)
    
    

        

            @if (Model.Lang.ToString() == "Fa")
            {
                English
                ?????
            }
            else
            {
                English
                ?????
            }
        
        @Html.Hidden("Lang")
    
    

        @Html.LabelFor(model => model.Name)
    
    

        @Html.EditorFor(model => model.Name)
        @Html.ValidationMessageFor(model => model.Name)
    

    

        @Html.LabelFor(model => model.Url)
    
    

        @Html.EditorFor(model => model.Url)
        @Html.ValidationMessageFor(model => model.Url)
    

    

        @Html.LabelFor(model => model.Title)
    
    

        @Html.EditorFor(model => model.Title)
        @Html.ValidationMessageFor(model => model.Title)
    

    

        @Html.LabelFor(model => model.PageContent)
    
    

        @Html.TextAreaFor(model => model.PageContent)
        @Html.ValidationMessageFor(model => model.PageContent)
    
    

        

            ???? ?????
        
        

            
        
    
    

        

            ??? ?????
        
        

            
        
    
    if (Model.PageAttachements!=null )
    {
    

        
???? ??? ?????
        

            @foreach (var file in Model.PageAttachements)
            {
                

                    ×
                    @file.Name
                
            }
        
    
    }
    if (Model.PageImages.Count > 0)
    {
    

        
?????? ?????
        

            @foreach (var image in Model.PageImages)
            {
                

                    ×
                    
                
            }
        
    
    }
    

        
    
}


@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}

和控制器:

public ActionResult Edit(int id)
{
    var model = Mapper.Map(pageApp.GetPageById(id));
    return View(model);
}
[HttpPost]
public ActionResult Edit(PageViewModel model)
{
    bool result = false;
    if (model.Lang.ToString() == "Fa")
        result = pageApp.IsRepetitive(model.Url, 1);
    else
        result = pageApp.IsRepetitive(model.Url, 2);
    if (result == true)
    {
        TempData["error"] = "???? ?? ?? ???? ???? ? ???? ???? ????.";
        return View();
    }
    else
    {
        if (model.PageContent != null)
        {
            var page = Mapper.Map(model);
            page.UserId = Portal.Web.CMS.Components.SessionContext.GetUserData().UserId;
            page.PageDate = DateTime.Now;
            pageApp.Update(page);
            TempData["success"] = "???? ?? ?????? ????? ????.";
            return RedirectToAction("Details", new { url = model.Url });
        }
        else
        {
            TempData["error"] = "????? ???.???? ???? ?? ???? ???.";
            return View();
        }
    }
}

CodingIntrig.. 8

在这些方面:

TempData["error"] = "????? ???.???? ???? ?? ???? ???.";
return View();

您将返回Edit没有模型的视图.因此,当您尝试在视图中访问模型时,会出现NullReferenceException.

您需要将相应的模型返回到视图:

return View(model);

旁注:由于您仍在使用强类型模型,因此您可能希望Error在模型中添加属性而不是使用TempData.