如何強制繼承類在其構造函數中實現方法？

Question

我遇到的問題是我有一堆從父類（BasePage）繼承的類（Pages）。任何時候我初始化一個子類，我還需要運行一個名爲WaitForLoadingToStop（）的方法。我如何繼承這個方法並將其實現到我的子類的構造函數中？

這就是我需要改變的地方，因爲它被複制到所有的地方，所以我希望這個在創建類時自動被繼承和執行。

 var assPage = new StudentAssesmentPage(Driver); 
     assPage.WaitForLoadingToStop(); 

這是一個示例子類，我有10人是這個樣子

public class StudentAssesmentPage : BasePage<StudentAssesmentPageObjectRepository> 
{ 
    public StudentAssesmentPage(IWebDriver driver) : base(driver, new StudentAssesmentPageObjectRepository(driver)) 
    {} 
} 

下面是我BasePage類

public abstract class BasePage<TObjectRepository> where TObjectRepository : BasePageObjectRepository 
{ 
    protected WebDriverWait Wait { get; } 
    protected IWebDriver Driver { get; } 
    protected ApplicationUrls ApplicationUrls { get; } 
    public IJavaScriptExecutor JavascriptExecutor { get; } 
    protected Actions UserInteractions { get; private set; } 

    protected By _loadingSpinnerLocator = By.Id("spinner"); 
    private readonly double LOADING_SPINNER_TIMEOUT = 60; 
    private TObjectRepository _objectRepository; 

    public BasePage(IWebDriver driver, TObjectRepository repository) 
    { 
     Driver = driver; 
     _objectRepository = repository; 
     UserInteractions = new Actions(Driver); 
     ApplicationUrls = new ApplicationUrls(); 
     Wait = new WebDriverWait(Driver, TimeSpan.FromSeconds(GetPageTimeout())); 
     JavascriptExecutor = Driver as IJavaScriptExecutor; 
    } 

    internal TObjectRepository ObjectRepository 
    { 
     get { return _objectRepository; } 
    } 

    protected bool WaitForLoadingToStop(int secondsToSleep = 5) 
    { 
     var sleepTime = TimeSpan.FromSeconds(secondsToSleep); 
     Reporter.Debug($"{Helpers.GetCurrentMethodName()}. Going to sleep for:{sleepTime.Seconds}"); 
     Thread.Sleep(sleepTime); 
     Reporter.Debug($"Now, going to wait for loading spinner for:{LOADING_SPINNER_TIMEOUT} seconds."); 
     var basePageWait = new WebDriverWait(Driver, TimeSpan.FromSeconds(LOADING_SPINNER_TIMEOUT)); 
     basePageWait.Message = 
      $"Waited for {LOADING_SPINNER_TIMEOUT}sec for the spinner. However, it took longer than that for the application to load."; 


     return basePageWait.Until(ExpectedConditions.InvisibilityOfElementLocated(By.XPath("//img[@src='/Content/images/spinner.gif']"))); 
    } 
} 

Answer 1

public class StudentAssesmentPage : BasePage<StudentAssesmentPageObjectRepository> 
{ 
    public StudentAssesmentPage(IWebDriver driver) : base(driver, new StudentAssesmentPageObjectRepository(driver)) 
    { 
     base.WaitForLoadingToStop(); 
    } 
} 

Answer 2

從基類只是繼承實現BasePageThatWaitsForLoadingToStop，它在構造函數中爲你完成工作。剩下的就是傳遞一個具體實施的構造函數的參數（如StudentAssesmentPage這個基類）

public class StudentAssesmentPage : BasePageThatWaitsForLoadingToStop 
{ 
    public StudentAssesmentPage(IWebDriver driver) : base(driver, new StudentAssesmentPageObjectRepository(driver)) // this is the only boilerplate code that is left 
    { 

    } 
} 

public class BasePageThatWaitsForLoadingToStop : BasePage<StudentAssesmentPageObjectRepository> 
{ 
    public BasePageThatWaitsForLoadingToStop(IWebDriver driver) : base(driver, new StudentAssesmentPageObjectRepository(driver)) 
    { 
     base.WaitForLoadingToStop(); 
    } 
} 

唯一的樣板代碼然後，您可以簡單地調用它，如下所示，它會自動執行爲您的工作：

var assPage = new StudentAssesmentPage(Driver); 

但是，請注意，從測試的角度來看，它是不理想的在構造函數中工作。