是否有可能擁有一個有條件的setter，超過0的值？

Question

如何將setter分配給條件值，例如大於0？如果值不爲0，我需要隱藏一個對象。最好的方法是什麼？任何ifeas高度讚賞。 DataTrigger的

XAML例如：

<DataTrigger Binding="{Binding Role.Count}" Value="0"> 
    <Setter TargetName="Counts" Property="Visibility" Value="Hidden" /> 
</DataTrigger> 

Answer 1

寫值轉換器，說IsGreaterThanZero，然後再編寫XAML爲，

<Window.Resources> 
     <local:IsGreaterThanZero x:Key="isGreaterThanZero"/> 
</Window.Resources> 

<DataTrigger Binding="{Binding Role.Count, Converter={StaticResource isGreaterThanZero}" Value="True"> 
    <Setter TargetName="Counts" Property="Visibility" Value="Hidden" /> 
</DataTrigger> 

而且IsGreaterThanZero可以寫成，

public class IsGreaterThanZero: IValueConverter 
{ 
     #region IValueConverter Members 
     public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
     { 
      return Int32.Parse(value as string) > 0; 
     } 

     public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
     { 
      throw new NotImplementedException() ;//"PresenterConverter.ConvertBack() is not implemented!"); 
     } 
     #endregion 
}