private void richTextBox1_TextChanged(object sender, EventArgs e)
{
richTextBox2.Text = "";
richTextBox1.SelectionAlignment = HorizontalAlignment.Left;
for (int i = 1; i < richTextBox1.Lines.Length; i++)
{
richTextBox2.Text += i.ToString() + '\r' + '\n';
}
var currentSelStart = richTextBox1.SelectionStart;
var currentSelLength = richTextBox1.SelectionLength;
richTextBox1.SelectAll();
richTextBox1.SelectionColor = SystemColors.WindowText;
bluend blue_obj = new bluend();
Yellow yellow_obj = new Yellow();
Orange orange_obj = new Orange();
blue_obj.check(richTextBox1);
yellow_obj.check(richTextBox1);
orange_obj.check(richTextBox1);
richTextBox1.Select(currentSelStart, currentSelLength);
richTextBox1.SelectionColor = SystemColors.WindowText;
}
