/////////////////////////////////////////////////////////////////////////////////////////////////////
// PUBLIC PROCEDURES
/////////////////////////////////////////////////////////////////////////////////////////////////////
/// <summary>
/// Returns the tag ranges that intersect with the specified normalized snapshot ranges.
/// </summary>
/// <param name="snapshotRanges">The collection of normalized snapshot ranges.</param>
/// <param name="parameter">An optional parameter that provides contextual information about the tag request.</param>
/// <returns>The tag ranges that intersect with the specified normalized snapshot ranges.</returns>
public override IEnumerable <TagSnapshotRange <IClassificationTag> > GetTags(NormalizedTextSnapshotRangeCollection snapshotRanges, object parameter)
{
// Loop through the requested snapshot ranges...
foreach (TextSnapshotRange snapshotRange in snapshotRanges)
{
// If the snapshot range is not zero-length...
if (!snapshotRange.IsZeroLength)
{
// Get a snapshot reader
ITextSnapshotReader reader = snapshotRange.Snapshot.GetReader(snapshotRange.StartOffset);
// If not already at the start of a line, back up to the start
if (!reader.IsAtSnapshotLineStart)
{
reader.GoToCurrentSnapshotLineStart();
}
// Read through the snapshot until the end of the target range is reached
while ((!reader.IsAtSnapshotEnd) && (reader.Offset < snapshotRange.EndOffset))
{
// Save the start of the line offset
int lineStartOffset = reader.Offset;
// Get the line start text (we need at most 6 chars for this sample)
string lineStartText = reader.PeekText(6);
// Go to the end of the line
reader.GoToCurrentSnapshotLineEnd();
// Add a range for the line if it starts with one of the defined strings...
// The StyleRegistryClassificationTag is a special ClassificationTag that allows you to indicate
// an alternate IHighlightingStyleRegistry to use for syntax highlighting... if using the
// normal AmbientHighlightingStyleRegistry, you'd just use a regular ClassificationTag instead
if (lineStartText.StartsWith("---"))
{
// Apply green to lines that start with "---"
yield return(new TagSnapshotRange <IClassificationTag>(
new TextSnapshotRange(snapshotRange.Snapshot, new TextRange(lineStartOffset, reader.Offset)),
new StyleRegistryClassificationTag(commentCT, styleRegistry)
));
}
else if (lineStartText.StartsWith("Error:"))
{
// Apply maroon to lines that start with "Error:"
yield return(new TagSnapshotRange <IClassificationTag>(
new TextSnapshotRange(snapshotRange.Snapshot, new TextRange(lineStartOffset, reader.Offset)),
new StyleRegistryClassificationTag(errorCT, styleRegistry)
));
}
// Consume the newline
reader.GoToNextSnapshotLineStart();
}
}
}
}
/// <summary>
/// Occurs when the link is clicked.
/// </summary>
/// <param name="sender">The sender of the event.</param>
/// <param name="e">A <see cref="RoutedEventArgs"/> that contains the event data.</param>
private void OnGoToCurrentLineStartHyperlinkClick(object sender, RoutedEventArgs e)
{
reader.Offset = editor.ActiveView.Selection.EndOffset;
reader.GoToCurrentSnapshotLineStart();
this.AppendMessageAndUpdateUI("Current line start", false);
}