53 lines
1.5 KiB
C#
53 lines
1.5 KiB
C#
// Copyright (c) 2017 schick Informatik
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// Description: Bool'sche Werte für Bindings invertieren
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//
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using System;
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using System.Windows.Data;
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using System.Windows.Markup;
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namespace ENI2.Util
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{
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[ValueConversion(typeof(bool?), typeof(bool?))]
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public class InverseBooleanConverter : MarkupExtension, IValueConverter
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{
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private static InverseBooleanConverter _converter = null;
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public override object ProvideValue(IServiceProvider serviceProvider)
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{
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if (_converter == null)
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{
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_converter = new InverseBooleanConverter();
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}
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return _converter;
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}
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#region IValueConverter Members
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public object Convert(object value, Type targetType, object parameter,
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System.Globalization.CultureInfo culture)
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{
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if (targetType != typeof(bool?))
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throw new InvalidOperationException("The target must be a boolean");
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if (!((bool?)value).HasValue) return null;
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return !(bool?)value;
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}
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public object ConvertBack(object value, Type targetType, object parameter,
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System.Globalization.CultureInfo culture)
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{
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if (targetType != typeof(bool?))
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throw new InvalidOperationException("The target must be a boolean");
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if (!((bool?)value).HasValue) return null;
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return !(bool?)value;
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}
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#endregion
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}
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}
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