ne kuzim.. nece mi
if (richTextBox3.Enabled == true)
            {
                if (richTextBox3.Text.Contains("return"))
                {
                    int index = richTextBox3.Find("return");
                    richTextBox3.Select(index, 6);
                    richTextBox3.SelectionColor = Color.Blue;
                }
            }
 
     
    
    
