HTML Editor Character color help

Question

Hey guys I'm making an HTML editor. I want to be able to have the HTML tags show up as a different color than the rest of the text. For example: Hello C#! I want the paragraph tags to be highlighted as a different color as the text (which is black by default). I was thinking of something like this. private void richTextBox1_TextChanged(object sender EventArgs e) { string text = richTextBox1.Text; char[] sep = { ' ' '
' '.' '' ':' ';' }; string[] words = text.Split(sep System.StringSplitOptions.RemoveEmptyEntries); for (int i = 0; i { if (text[i] == ' { //change color of tag here } } } Thats just a rough idea. I know I'm gonna have to add code that will loop through the text and when it finds the ' ' character is found. I know it needs a lot of work but I'm kinda new at this. Any suggestions or help. If I can get this to work I would be so happy. I've been messing with it for a while. Please let me know. -Dave

David Pullman · Answer

thanks a lot for all the help i appreciate it.

Stefan · Answer

Hey David I'm glad you got it to work. To stop the flashing add this namespace: using System.Runtime.Interop; Next Modify your code to look like this: namespace WindowsFormsApplication3 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } [DllImport(user32.dll)] public static extern bool LockWindowUpdate(IntrPtr hWndLock); private void richTextBox1_TextChanged(object sender EventArgs e) { try { LockWindowUpdate(richTextBox1.Handle); Regex tags = new Regex( ]*> RegexOptions.IgnoreCase); int selPos = richTextBox1.SelectionStart; int selLength = richTextBox1.SelectionLength; foreach (Match match in tags.Matches(richTextBox1.Text)) { richTextBox1.Select(match.Index match.Length); richTextBox1.SelectionColor = Color.Blue; richTextBox1.SelectionStart = selPos; richTextBox1.SelectionLength = selLength; richTextBox1.SelectionColor = Color.Black; } } finally { LockWindowUpdate(IntPtr.Zero); } } } }

David Pullman · Answer

Hey I figured it out. Could anyone please tell me how to stop the flickering? I search for over an hour but haven't found anything that I understand. Here is my code so far: using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.IO; using System.Text.RegularExpressions; namespace WindowsFormsApplication3 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void richTextBox1_TextChanged(object sender EventArgs e) { Regex tags = new Regex( ]*> RegexOptions.IgnoreCase); int selPos = richTextBox1.SelectionStart; int selLength = richTextBox1.SelectionLength; foreach (Match match in tags.Matches(richTextBox1.Text)) { richTextBox1.Select(match.Index match.Length); richTextBox1.SelectionColor = Color.Blue; richTextBox1.SelectionStart = selPos; richTextBox1.SelectionLength = selLength; richTextBox1.SelectionColor = Color.Black; } } } }

Stefan · Answer

Yes the foreach loop goes in the text-changed event for the rich text box. The regex can be placed at the top of the class or inside of the text-changed event. You said you tried that but it did not work. Could you be more specific? Was there an error? Did the text just not change color? Please post back and I'll try to help.

David Pullman · Answer

Hey guys one more question. Do I put the regex and foreach code in this section? private void richTextBox1_TextChanged(object sender EventArgs e) { } I tried that and it didn't work. Please let me know.

Stefan · Answer

Try this: Regex tags = new Regex( ]*>) RegexOptions.IgnoreCase; int selPos = richTexBox1.SelectionStart; int selLength = richTextBox1.SelectionLength; foreach (Match match in tags.Matches(richTextBox1.Text)) { richTextBox1.Select(match.Index match.Length); richTextBox1.SelectionColor = Color.Blue; richTextBox1.SelectionStart = selPos; richTextox1.SelectionLength = selLength; richTextBox1.SelectionColor = Color.Black; } This uses regex to find a matches (any code inside of a  ) and colors it. You may notice some flashing. To stop this you'll need to stop the rich text box from updating. Hope this helps.

David Pullman · Answer

no help yet? sorry i'm really anxious