private static void Swap(HighlightTextBlock tb)
{
Brush temp;
temp = tb.Background;
tb.Background = tb.HighlightBackground;
tb.HighlightBackground = temp;
temp = tb.Foreground;
tb.Foreground = tb.HighlightForeground;
tb.HighlightForeground = temp;
temp = null;
}
private static void MatchWholeWordPropertyChanged(DependencyObject sender,
DependencyPropertyChangedEventArgs e)
{
//getting the current instance of Textblock
HighlightTextBlock tb = sender as HighlightTextBlock;
if (!(bool)e.NewValue)
{
if (tb.Highlighted)
{
Swap(tb);
tb.Highlighted = false;
}
}
}
/// <summary>
/// Callback method when user search is changed.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private static void HighlightTextChanged(DependencyObject sender,
DependencyPropertyChangedEventArgs e)
{
//getting the current instance of Textblock
HighlightTextBlock tb = sender as HighlightTextBlock;
string completeText = tb.Text.Trim();
string searchText = e.NewValue.ToString().Trim();
//Check if string case hase to be considered.
if (!tb.MatchCase)
{
completeText = completeText.ToLower();
searchText = searchText.ToLower();
}
//Check if we need to compare the whole word.
if (tb.MatchWholeWord)
{
if (completeText != string.Empty)
{
//when the condition is true,
//set the highlight color specified by customer.
if (completeText == searchText)
{
// we swap the colors so reset when no search text is passed.
Swap(tb);
tb.Highlighted = true;
}
else
{
if (tb.Highlighted)
{
Swap(tb);
tb.Highlighted = false;
}
}
}
}
else
{
int endIndex = completeText.Length;
int highlightStartIndex = completeText.IndexOf(searchText);
completeText = tb.Text.Trim();
tb.Inlines.Clear();
if (highlightStartIndex >= 0)
{
int highlightTextLength = searchText.Length;
int highlightEndIndex = highlightStartIndex + highlightTextLength;
tb.Inlines.Add(completeText.Substring(0, highlightStartIndex));
tb.Inlines.Add(new Run()
{
Text = completeText.Substring(highlightStartIndex, highlightTextLength),
Foreground = tb.HighlightForeground,
Background = tb.HighlightBackground
});
tb.Inlines.Add(completeText.Substring
(highlightEndIndex,
endIndex - highlightEndIndex));
}
else
{
tb.Inlines.Add(completeText);
}
}
}
