内置 BooleanToVisibilityConverter IValueConverter
布尔值和可见性之间的转换。获取输入的 bool
值并返回 Visibility
值。
注意:此转换器已存在于 System.Windows.Controls
命名空间中
public sealed class BooleanToVisibilityConverter : IValueConverter
{
/// <summary>
/// Convert bool or Nullable bool to Visibility
/// </summary>
/// <param name="value">bool or Nullable bool</param>
/// <param name="targetType">Visibility</param>
/// <param name="parameter">null</param>
/// <param name="culture">null</param>
/// <returns>Visible or Collapsed</returns>
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
bool bValue = false;
if (value is bool)
{
bValue = (bool)value;
}
else if (value is Nullable<bool>)
{
Nullable<bool> tmp = (Nullable<bool>)value;
bValue = tmp.HasValue ? tmp.Value : false;
}
return (bValue) ? Visibility.Visible : Visibility.Collapsed;
}
/// <summary>
/// Convert Visibility to boolean
/// </summary>
/// <param name="value"></param>
/// <param name="targetType"></param>
/// <param name="parameter"></param>
/// <param name="culture"></param>
/// <returns></returns>
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
if (value is Visibility)
{
return (Visibility)value == Visibility.Visible;
}
else
{
return false;
}
}
}
使用转换器
- 定义资源
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
- 在绑定中使用它
<Button Visibility="{Binding AllowEditing,
Converter={StaticResource BooleanToVisibilityConverter}}"/>