public BracketsHighlighter(TextEditor textEditor)
{
_bracketsStarting = new char[] { '{', '(', '[' };
_bracketsEnding = new char[] { '}', ')', ']' };
_textEditor = textEditor;
_bracketsMatch = null;
_textEditor.TextArea.Caret.PositionChanged -= Caret_PositionChanged;
_textEditor.TextArea.Caret.PositionChanged += Caret_PositionChanged;
_bracketsColorizingTransformer = new BracketsColorizingTransformer();
_textEditor.TextArea.TextView.LineTransformers.Add(_bracketsColorizingTransformer);
}
// Event rased every time caret is changed in document.
private void Caret_PositionChanged(object sender, EventArgs eventArgs)
{
Caret caret = sender as Caret;
if (_bracketsMatch != null)
{
_bracketsColorizingTransformer.Locations.Clear();
_textEditor.TextArea.TextView.Redraw();
_bracketsMatch = null;
}
int caretOffset = _textEditor.Document.GetOffset(caret.Location);
char textBefore = '\0';
char textAfter = '\0';
try
{
textAfter = _textEditor.Text[caretOffset];
textBefore = _textEditor.Text[caretOffset - 1];
} catch
{
return;
}
if (_bracketsEnding.Contains(textBefore))
{
char searchFor = _bracketsStarting[Array.IndexOf(_bracketsEnding, textBefore)];
_bracketsMatch = FindMatchingBrackets(caretOffset - 1, searchFor, textBefore);
}
else if (_bracketsStarting.Contains(textAfter))
{
char searchFor = _bracketsEnding[Array.IndexOf(_bracketsStarting, textAfter)];
_bracketsMatch = FindMatchingBrackets(caretOffset + 1, textAfter, searchFor);
}
if (_bracketsMatch != null)
{
TextLocation openingLine = _textEditor.Document.GetLocation(_bracketsMatch.OpeningOffset);
TextLocation closingLine = _textEditor.Document.GetLocation(_bracketsMatch.ClosingOffset);
_bracketsColorizingTransformer.Locations.Add(openingLine);
_bracketsColorizingTransformer.Locations.Add(closingLine);
_textEditor.TextArea.TextView.Redraw(_bracketsMatch.OpeningOffset, _bracketsMatch.ClosingOffset - _bracketsMatch.OpeningOffset);
}
}
