如何用Moq单元测试HtmlHelper？

Question

有人能告诉我你将如何去创建一个模拟HTML助手与Moq？

这article有一个链接到一篇文章，声称来形容这一点，但仅之后返回一个ASP.NET运行时错误的链接

[编辑] 我问有关同一主题的一个更具体的问题here，但没有得到任何回应。我认为它太具体了，所以我认为我可以对一个更一般的问题得到更一般的答案，并对其进行修改以满足我的要求。

感谢

Answer 1

你可以做的是这样的：

HtmlHelper helper = null; 
helper.YourHelperMethod(); 

无需要嘲笑任何东西。对我而言非常出色。

Answer 2

Here的另一篇文章，告诉您如何来实现同样的事情：

public static HtmlHelper CreateHtmlHelper(ViewDataDictionary vd) 
{ 
    var mockViewContext = new Mock<ViewContext>(
    new ControllerContext(
     new Mock<HttpContextBase>().Object, 
     new RouteData(), 
     new Mock<ControllerBase>().Object), 
    new Mock<IView>().Object, 
    vd, 
    new TempDataDictionary()); 

    var mockViewDataContainer = new Mock<IViewDataContainer>(); 
    mockViewDataContainer.Setup(v => v.ViewData).Returns(vd); 

    return new HtmlHelper(mockViewContext.Object, mockViewDataContainer.Object); 
} 

Answer 3

在MVC5中，ViewContext具有TextWriter的额外构造函数参数，因此Thomas的代码不再有效。我加了一个内存中的TextWriter来解决这个问题：

public static HtmlHelper CreateHtmlHelper(ViewDataDictionary vd) 
{ 
    Mock<ViewContext> mockViewContext = new Mock<ViewContext>(
     new ControllerContext(
      new Mock<HttpContextBase>().Object, 
      new RouteData(), 
      new Mock<ControllerBase>().Object 
     ), 
     new Mock<IView>().Object, 
     vd, 
     new TempDataDictionary(), 
     new StreamWriter(new MemoryStream()) 
    ); 

    Mock<IViewDataContainer> mockDataContainer = new Mock<IViewDataContainer>(); 
    mockDataContainer.Setup(c => c.ViewData).Returns(vd); 

    return new HtmlHelper(mockViewContext.Object, mockDataContainer.Object); 
} 

Answer 4

为了测试一次性帮手像BeginForm与访问ViewContext.Writer您可以使用此：

public static HtmlHelper CreateHtmlHelper(ViewDataDictionary vd, Stream stream = null) 
{ 
    TextWriter textWriter = new StreamWriter(stream ?? new MemoryStream()); 
    Mock<ViewContext> mockViewContext = new Mock<ViewContext>(
     new ControllerContext(
      new Mock<HttpContextBase>().Object, 
      new RouteData(), 
      new Mock<ControllerBase>().Object 
     ), 
     new Mock<IView>().Object, 
     vd, 
     new TempDataDictionary(), 
     textWriter 
    ); 
    mockViewContext.Setup(vc => vc.Writer).Returns(textWriter); 

    Mock<IViewDataContainer> mockDataContainer = new Mock<IViewDataContainer>(); 
    mockDataContainer.Setup(c => c.ViewData).Returns(vd); 

    return new HtmlHelper(mockViewContext.Object, mockDataContainer.Object); 
}