public override VisualLineElement ConstructElement(int offset)
{
var c = CurrentContext.Document.GetCharAt(offset);
if (ShowSpaces && c == ' ')
{
return(new SpaceTextElement(CurrentContext.TextView.CachedElements.GetTextForNonPrintableCharacter("\u00B7", CurrentContext)));
}
if (ShowTabs && c == '\t')
{
return(new TabTextElement(CurrentContext.TextView.CachedElements.GetTextForNonPrintableCharacter("\u00BB", CurrentContext)));
}
if (ShowBoxForControlCharacters && char.IsControl(c))
{
var p = CurrentContext.GlobalTextRunProperties.Clone();
p.ForegroundBrush = Brushes.White;
var textFormatter = TextFormatterFactory.Create();
var text = FormattedTextElement.PrepareText(textFormatter,
TextUtilities.GetControlCharacterName(c), p);
return(new SpecialCharacterBoxElement(text));
}
return(null);
}
public TextLine GetTextForNonPrintableCharacter(string text, ITextRunConstructionContext context)
{
if (_nonPrintableCharacterTexts == null)
{
_nonPrintableCharacterTexts = new Dictionary <string, TextLine>();
}
if (_nonPrintableCharacterTexts.TryGetValue(text, out var textLine))
{
return(textLine);
}
var properties = context.GlobalTextRunProperties.Clone();
properties.ForegroundBrush = context.TextView.NonPrintableCharacterBrush;
if (_formatter == null)
{
_formatter = TextFormatterFactory.Create();
}
textLine = FormattedTextElement.PrepareText(_formatter, text, properties);
_nonPrintableCharacterTexts[text] = textLine;
return(textLine);
}
public SpecialCharacterTextRun(FormattedTextElement element, TextRunProperties properties)
: base(element, properties)
{
}
/// <summary>
/// Creates a new FormattedTextRun.
/// </summary>
public FormattedTextRun(FormattedTextElement element, TextRunProperties properties)
{
Properties = properties ?? throw new ArgumentNullException(nameof(properties));
Element = element ?? throw new ArgumentNullException(nameof(element));
}