Question

我正在按照本书的步骤进行操作：“大脑友好指南：Head First C＃＆＃39;作者：O＆＃39; Reilly Media

并且遇到了此错误'Windows.UI.Xaml.Duration' is a 'type' but is used like a 'variable'

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

时

我想知道为什么我会收到此错误，我该怎么做才能修复它？

下面是书中描述的完整代码方法，如果它有帮助，如果它只是造成混乱并且使用户难以阅读文本我将删除该方法。

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

编译器试图告诉您，您不能使用类型Duration的名称来命名匿名类型的字段，因为您的初始化程序语法不正确：您在new DoubleAnimation()之后添加了分号，因此初始化程序的其余部分被视为独立的代码块。

这是正确的语法：

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

我在new DoubleAnimation之后删除了括号，因为调用了默认构造函数。我还用逗号替换了分号以符合C＃语法。

Answer 2

正如Jesse所指出的那样，你应该删除分号并用逗号替换它们：

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();
            }

C＃Duration是一种类型，但像变量一样使用

2 个答案: