我一直在努力通过Scott Guthrie在
ASP.NET MVC Beta 1的优秀帖子.在其中他展示了对UpdateModel方法的改进以及它们如何改进单元测试.我已经重新创建了一个类似的项目,但是当我运行包含对UpdateModel的调用的UnitTest时,我会收到一个名为controllerContext参数的ArgumentNullException.
这是相关的位,从我的模型开始：
public class Country {
public Int32 ID { get; set; }
public String Name { get; set; }
public String Iso3166 { get; set; }
}
控制器动作：
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Edit(Int32 id,FormCollection form)
{
using ( ModelBindingDataContext db = new ModelBindingDataContext() ) {
Country country = db.Countries.Where(c => c.CountryID == id).SingleOrDefault();
try {
UpdateModel(country,form);
db.SubmitChanges();
return RedirectToAction("Index");
}
catch {
return View(country);
}
}
}
最后我的单元测试失败了：
[TestMethod]
public void Edit()
{
CountryController controller = new CountryController();
FormCollection form = new FormCollection();
form.Add("Name","Canada");
form.Add("Iso3166","CA");
var result = controller.Edit(2 /*Canada*/,form) as RedirectToRouteResult;
Assert.IsNotNull(result,"Expected to be redirected on successful POST.");
Assert.AreEqual("Show",result.RouteName,"Expected to redirect to the View action.");
}
调用UpdateModel时抛出ArgumentNullException,消息“Value not not null.参数名称：controllerContext”.我假设某个地方UpdateModel需要System.Web.Mvc.ControllerContext,它在执行测试期间不存在.
我也假设我在某处做错了,只需指向正确的方向.
请帮忙！
解决方法
我不认为可以这样做,因为UpdateModel使用的TryUpdateModel引用了ControllerContext,当从单元测试调用时它是null.我使用RhinoMocks来模拟或存根控制器所需的各种组件.
var routeData = new RouteData();
var httpContext = MockRepository.GenerateStub<HttpContextBase>();
FormCollection formParameters = new FormCollection();
EventController controller = new EventController();
ControllerContext controllerContext =
MockRepository.GenerateStub<ControllerContext>( httpContext,routeData,controller );
controller.ControllerContext = controllerContext;
ViewResult result = controller.Create( formParameters ) as ViewResult;
Assert.AreEqual( "Event",result.Values["controller"] );
Assert.AreEqual( "Show",result.Values["action"] );
Assert.AreEqual( 0,result.Values["id"] );
以下是www.codeplex.com/aspnet上Controller.cs源代码中的相关位：
protected internal bool TryUpdateModel<TModel>( ... ) where TModel : class
{
....
ModelBindingContext bindingContext =
new ModelBindingContext( ControllerContext,valueProvider,typeof(TModel),prefix,() => model,ModelState,propertyFilter );
...
}
