WPF/XAML: How to make all text upper case in TextBlock?

Question

I want all characters in a TextBlock to be displayed in uppercase

Answer 1

Implement a custom converter.

using System.Globalization;
using System.Windows.Data;
// ...
public class StringToUpperConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value != null && value is string )
        {
            return ((string)value).ToUpper();
        }

        return value;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return null;
    }
}

Then include that in your XAML as a resource:

<local:StringToUpperConverter  x:Key="StringToUpperConverter"/>

And add it to your binding:

Converter={StaticResource StringToUpperConverter}

Answer 2

You can use an attached property like this:

public static class TextBlock
{
    public static readonly DependencyProperty CharacterCasingProperty = DependencyProperty.RegisterAttached(
        "CharacterCasing",
        typeof(CharacterCasing),
        typeof(TextBlock),
        new FrameworkPropertyMetadata(
            CharacterCasing.Normal,
            FrameworkPropertyMetadataOptions.Inherits | FrameworkPropertyMetadataOptions.NotDataBindable,
            OnCharacterCasingChanged));

    private static readonly DependencyProperty TextProxyProperty = DependencyProperty.RegisterAttached(
        "TextProxy",
        typeof(string),
        typeof(TextBlock),
        new PropertyMetadata(default(string), OnTextProxyChanged));

    private static readonly PropertyPath TextPropertyPath = new PropertyPath("Text");


    public static void SetCharacterCasing(DependencyObject element, CharacterCasing value)
    {
        element.SetValue(CharacterCasingProperty, value);
    }

    public static CharacterCasing GetCharacterCasing(DependencyObject element)
    {
        return (CharacterCasing)element.GetValue(CharacterCasingProperty);
    }

    private static void OnCharacterCasingChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        if (d is System.Windows.Controls.TextBlock textBlock)
        {
            if (BindingOperations.GetBinding(textBlock, TextProxyProperty) == null)
            {
                BindingOperations.SetBinding(
                    textBlock,
                    TextProxyProperty,
                    new Binding
                    {
                        Path = TextPropertyPath,
                        RelativeSource = RelativeSource.Self,
                        Mode = BindingMode.OneWay,
                    });
            }
        }
    }

    private static void OnTextProxyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        d.SetCurrentValue(System.Windows.Controls.TextBlock.TextProperty, Format((string)e.NewValue, GetCharacterCasing(d)));

        string Format(string text, CharacterCasing casing)
        {
            if (string.IsNullOrEmpty(text))
            {
                return text;
            }

            switch (casing)
            {
                case CharacterCasing.Normal:
                    return text;
                case CharacterCasing.Lower:
                    return text.ToLower();
                case CharacterCasing.Upper:
                    return text.ToUpper();
                default:
                    throw new ArgumentOutOfRangeException(nameof(casing), casing, null);
            }
        }
    }
}

Then usage in xaml will look like:

<StackPanel>
    <TextBox x:Name="TextBox" Text="abc" />
    <TextBlock local:TextBlock.CharacterCasing="Upper" Text="abc" />
    <TextBlock local:TextBlock.CharacterCasing="Upper" Text="{Binding ElementName=TextBox, Path=Text}" />
    <Button local:TextBlock.CharacterCasing="Upper" Content="abc" />
    <Button local:TextBlock.CharacterCasing="Upper" Content="{Binding ElementName=TextBox, Path=Text}" />
</StackPanel>

Answer 3

If it's not a big deal you could use TextBox instead of TextBlock like this:

<TextBox CharacterCasing="Upper" IsReadOnly="True" />

Answer 4

How about a Converter that converts your text to uppercase. This way you original text stays unchanged.

How to use IValueConverter in Binding of WPF

Answer 5

I use a character casing value converter:

class CharacterCasingConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        var s = value as string;
        if (s == null)
            return value;

        CharacterCasing casing;
        if (!Enum.TryParse(parameter as string, out casing))
            casing = CharacterCasing.Upper;

        switch (casing)
        {
            case CharacterCasing.Lower:
                return s.ToLower(culture);
            case CharacterCasing.Upper:
                return s.ToUpper(culture);
            default:
                return s;
        }
    }

    object IValueConverter.ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotSupportedException();
    }
}

Answer 6

Or use

Typography.Capitals="AllSmallCaps"

in your TextBlock definition.

See here: MSDN - Typography.Capitals

EDIT:

This does not work in Windows Phone 8.1, only in Windows 8.1 ...