如何用Moq單元測試HtmlHelper？

Question

有人能告訴我你將如何去創建一個模擬HTML助手與Moq？

這article有一個鏈接到一篇文章，聲稱來形容這一點，但僅之後返回一個ASP.NET運行時錯誤的鏈接

[編輯] 我問有關同一主題的一個更具體的問題here，但沒有得到任何迴應。我認爲它太具體了，所以我認爲我可以對一個更一般的問題得到更一般的答案，並對其進行修改以滿足我的要求。

感謝

Answer 1

你可以做的是這樣的：

HtmlHelper helper = null; 
helper.YourHelperMethod(); 

無需要嘲笑任何東西。對我而言非常出色。

Answer 2

Here的另一篇文章，告訴您如何來實現同樣的事情：

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的額外構造函數參數，因此Thomas的代碼不再有效。我加了一個內存中的TextWriter來解決這個問題：

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

爲了測試一次性幫手像BeginForm與訪問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); 
}