ObservableCollection的可见性IValueConverter [重复](Visibility IValueConverter for ObservableCollection [d

ObservableCollection的可见性IValueConverter [重复](Visibility IValueConverter for ObservableCollection [duplicate])

这个问题在这里已有答案：

EmptyListToVisibilityConverter 6回答

我想创建一个可见性转换器，如果observablecollection为空或null，则显示内容。 由于此转换器将在许多屏幕上使用，因此每个集合将保持不同的类型（T）。

如何获取未知类型的ObservableCollection的引用。 这是我到目前为止：

public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { if (value == null) return Visibility.Visible; if (value is ObservableCollection<object>) { var col = value as ObservableCollection<object>; return col.Count > 0 ? Visibility.Hidden : Visibility.Visible; } return Binding.DoNothing; }

This question already has an answer here:

EmptyListToVisibilityConverter 6 answers

I'd like to create a visibility converter which displays content if an observablecollection is empty or null. As this converter will be used on many screens, each collection will hold a different type (T).

How do I get a reference to the ObservableCollection of unknown type. This is what I have so far:

public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { if (value == null) return Visibility.Visible; if (value is ObservableCollection<object>) { var col = value as ObservableCollection<object>; return col.Count > 0 ? Visibility.Hidden : Visibility.Visible; } return Binding.DoNothing; }

最满意答案

你不必。 只需转换为ICollection并获取其Count 。

You don't have to. Just cast to ICollection and get its Count.