How To Color Spacific Char Charters In Rich Text Box?

Question

Hello im working on a program that displays a gui with all the keyboard keys and a rich text box in C# windoes forms,
the user is supposed to input a text to the rich text box and then press with the mouse (for exmple) the A button
and all the a the a chars will be in green color,but i dont know how can i color those specific car charcters.

any help would be more than appreciated

Vulpes · Answer

Try handling the RTB's MouseDown event as follows: private void richTextBox1_MouseDown(object sender MouseEventArgs e) { char find = Char.ToLower(richTextBox1.GetCharFromPosition(e.Location)); char find2 = Char.ToUpper(find); for (int i = 0; i { if (richTextBox1.Text[i] == find || richTextBox1.Text[i] == find2) { richTextBox1.SelectionStart = i; richTextBox1.SelectionLength = 1; richTextBox1.SelectionColor = Color.Red; } } richTextBox1.SelectionStart = richTextBox1.Text.Length; richTextBox1.SelectionLength = 0; richTextBox1.SelectionColor = Color.Black; }