WPF技巧-常用的Converter集合(更新ing)

🧩 示例 1：BooleanToVisibilityConverter

将布尔值转换为 Visibility（如 true => Visible, false => Collapsed）

public class BooleanToVisibilityConverter : IValueConverter
{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){if (value is bool booleanValue)return booleanValue ? Visibility.Visible : Visibility.Collapsed;return Visibility.Collapsed;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){if (value is Visibility visibility)return visibility == Visibility.Visible;return false;}
}

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🧩 示例 2：InvertedBooleanToVisibilityConverter

反向布尔转可见性（true => Collapsed, false => Visible）

public class InvertedBooleanToVisibilityConverter : IValueConverter
{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){if (value is bool booleanValue)return !booleanValue ? Visibility.Visible : Visibility.Collapsed;return Visibility.Visible;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){if (value is Visibility visibility)return visibility != Visibility.Visible;return true;}
}

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🧩 示例 3：StringToColorConverter

将字符串转换为 Color（支持 Hex、Named 等格式）

public class StringToColorConverter : IValueConverter
{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){if (value is string colorStr){try{return (Color)ColorConverter.ConvertFromString(colorStr);}catch { }}return Colors.Transparent;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){if (value is Color color)return color.ToString();return string.Empty;}
}

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🧩 示例 4：StringToBrushConverter

将字符串转换为 Brush（支持 Hex、Named）

public class StringToBrushConverter : IValueConverter
{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){if (value is string brushStr){try{return new SolidColorBrush((Color)ColorConverter.ConvertFromString(brushStr));}catch { }}return Brushes.Transparent;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){if (value is SolidColorBrush brush)return brush.Color.ToString();return string.Empty;}
}

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🧩 示例 5：NullToVisibilityConverter

将 null 或空对象转换为 Visibility（非空显示，为空隐藏）

public class NullToVisibilityConverter : IValueConverter
{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){return value == null || value is string str && string.IsNullOrEmpty(str)? Visibility.Collapsed: Visibility.Visible;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){throw new NotImplementedException();}
}

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🧩 示例 6：EnumToVisibilityConverter

根据枚举值是否匹配某个参数来决定是否显示

public class EnumToVisibilityConverter : IValueConverter
{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){if (value == null || parameter == null)return Visibility.Collapsed;return value.ToString() == parameter.ToString()? Visibility.Visible: Visibility.Collapsed;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){if (value is Visibility visible && visible == Visibility.Visible && parameter != null)return parameter;return Binding.DoNothing;}
}

XAML 使用：

<TextBlock Text="Only shown when Status is Active"Visibility="{Binding Status, Converter={StaticResource EnumToVisibilityConverter}, ConverterParameter=Active}" />

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🧩 示例 7：DoubleToOpacityConverter

将数值映射为透明度（0.0 - 1.0）

public class DoubleToOpacityConverter : IValueConverter
{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){if (value is double opacity)return opacity >= 0 && opacity <= 1 ? opacity : 1.0;return 1.0;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){if (value is double opacity)return opacity;return 1.0;}
}

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✅ 注册与使用方式（XAML）

1. 在资源中注册：

<Window.Resources><converters:BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter" /><converters:StringToBrushConverter x:Key="StringToBrushConverter" /><!-- 其他转换器 -->
</Window.Resources>

2. 在绑定中使用：

<Button Content="Toggle" Visibility="{Binding IsEnabled, Converter={StaticResource BooleanToVisibilityConverter}}" /><TextBlock Text="Colored Text"Foreground="{Binding TextColor, Converter={StaticResource StringToBrushConverter}}" />