Syntax highlighting in richtextbox

Question

How do i highlight the CSS keywords in richtextbox using c#? I had css parser to split the selector, property and value and used following code for this purpose,          CssParser parser = new CssParser();             var rules = parser.ParseAll(RichEditor.Text);             StringBuilder selectorBuilder = new StringBuilder();              StringBuilder propertyBuilder = new StringBuilder();             StringBuilder ValueBuilder = new StringBuilder();             Regex selectorRegex, mediaRegex, propertyRegex, valueRegex;             int cursorPosition = RichEditor.SelectionStart;             int lineIndex = RichEditor.GetLineFromCharIndex(cursorPosition);
foreach (var rule in rules)             {
foreach (var selector in rule.Selectors)                 {                                        selectorBuilder.Append(selector.ToString() + "|");                 }                 if (rule.Media != null)                 {                     mediaBuilder.Append(rule.Media.ToString() + "|");                 }                 foreach (var declaration in rule.Declarations)                 {                     propertyBuilder.Append(declaration.Property.ToString() + "|");                      ValueBuilder.Append(declaration.Value.ToString() + "|");                 }
}
selectorRegex = new Regex(selectorBuilder.ToString());             mediaRegex = new Regex(mediaBuilder.ToString());             propertyRegex = new Regex(propertyBuilder.ToString());             valueRegex = new Regex(ValueBuilder.ToString());
// Select all and set to black so that it's 'clean'             RichEditor.SelectAll();             RichEditor.SelectionColor = System.Drawing.Color.Black;
// Then unselect and scroll to the end of the file             RichEditor.ScrollToCaret();             RichEditor.Select(RichEditor.Text.Length, 1);
// Start applying the highlighting... Set a value to selPos             int selPos = RichEditor.SelectionStart;
foreach (Match keyWordMatch in selectorRegex.Matches(RichEditor.Text))             {                                RichEditor.Select(keyWordMatch.Index, keyWordMatch.Length);                               RichEditor.SelectionColor = System.Drawing.Color.Brown;                                RichEditor.SelectionStart = selPos;                              }
selPos = RichEditor.SelectionStart;
foreach (Match keyWordMatch in mediaRegex.Matches(RichEditor.Text))             {                                RichEditor.Select(keyWordMatch.Index, keyWordMatch.Length);                                RichEditor.SelectionColor = System.Drawing.Color.Red;                                RichEditor.SelectionStart = selPos;                             }
selPos = RichEditor.SelectionStart;
foreach (Match keyWordMatch in propertyRegex.Matches(RichEditor.Text))             {                                 RichEditor.Select(keyWordMatch.Index, keyWordMatch.Length);                            RichEditor.SelectionColor = System.Drawing.Color.Red;                                 RichEditor.SelectionStart = selPos;                             }
selPos = RichEditor.SelectionStart;
foreach (Match keyWordMatch in valueRegex.Matches(RichEditor.Text))             {                           RichEditor.Select(keyWordMatch.Index, keyWordMatch.Length);                         RichEditor.SelectionColor = System.Drawing.Color.Blue;                               RichEditor.SelectionStart = selPos;                                RichEditor.SelectionColor = System.Drawing.Color.Black;             }    But every time the text in richtextbox is flickering. Is there any solution for this purpose?

vijay mani · Answer

No,Its a windows form application.

Francis Susaimichael · Answer

Seems that you are using server side code. Instead of that i suggest to use Clientside Javascript libraries, which can provide a good user experience. Try to consider this JS library to achieve your goal.