C＃持續時間是一個類型，但使用像變量

Question

我下面這本書的步驟「腦友好的嚮導：深入淺出C＃」由O'Reilly媒體

而且所遇到的這個錯誤'Windows.UI.Xaml.Duration' is a 'type' but is used like a 'variable'

當插入此代碼Duration = new Duration(TimeSpan.FromSeconds(random.Next(4, 6)));

我想知道爲什麼我得到這個錯誤，我能做些什麼來解決它？

下面是代碼的完整方法，如果它有幫助，如果它只是造成混亂，並使用戶難以閱讀文本，我將刪除該方法已被描述在書中。

private void AnimateEnemy(ContentControl enemy, double from, double to, string propertyToAnimate) 
     { 
      Storyboard storyboard = new Storyboard() { AutoReverse = true, RepeatBehavior = RepeatBehavior.Forever }; 
      DoubleAnimation animation = new DoubleAnimation(); 
      { 
       From = from; 
       To = to; 
       Duration = new Duration(TimeSpan.FromSeconds(random.Next(4, 6))) 
      }; 
      Storyboard.SetTarget(animation, enemy); 
      Storyboard.SetTargetProperty(animation, propertyToAnimate); 
      storyboard.Children.Add(animation); 
      storyboard.Begin(); 
      } 

Answer 1

編譯器是想告訴你，你不能在匿名類型與類型Duration的名字命名一個字段，因爲你的初始化語法是不正確的：你把分號new DoubleAnimation()後，所以的休息初始化器被視爲獨立的代碼塊。

下面是正確的語法：

DoubleAnimation animation = new DoubleAnimation { 
    From = from, 
    To = to, 
    Duration = new Duration(TimeSpan.FromSeconds(random.Next(4, 6))) 
}; 

我去掉括號new DoubleAnimation後，因爲調用的是默認的構造函數取得。我還用逗號替換了分號以符合C＃語法。

Answer 2

傑西指出，應刪除分號，並用逗號替換它們：

private void AnimateEnemy(ContentControl enemy, double from, double to, string propertyToAnimate) 
     { 
      Storyboard storyboard = new Storyboard() { AutoReverse = true, RepeatBehavior = RepeatBehavior.Forever }; 
      DoubleAnimation animation = new DoubleAnimation() 
      { 
       From = from, 
       To = to, 
       Duration = new Duration(TimeSpan.FromSeconds(random.Next(4, 6))) 
      }; 
       Storyboard.SetTarget(animation, enemy); 
       storyboard.SetTargetProperty(animation, propertyToAnimate); 
       storyboard.Children.Add(animation); 
       storyboard.Begin(); 
      }