string GetEmailFromText (string Txt)
{
    /* Extract first email address from the text Txt */
    original_text = input.Txt;
    EMAIL_REGEX = ("[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?");
    masked_text1 = original_text.replaceFirst(EMAIL_REGEX,"##EML##");
    masked_text2 = original_text.replaceFirst(EMAIL_REGEX,"");
    email_address_position = masked_text1.indexOf("##EML##");
    email_address_length = (input.Txt.length() - masked_text2.length());
    email_address = original_text.subString(email_address_position,(email_address_position + email_address_length));
    return email_address;
}