regexp

Regular expressions are a powerful text transformation tool. The example below lets you conditionally display some text when the subject of the message contains either free or gratis strings:

<if condition="System.Text.RegularExpressions.Regex.IsMatch(MessageSubject, 'free|gratis')">
    <p>New wonderful free offer for our clients!</p>
</if>

Regular expressions allow you to replace one string with the other. Example below replaces string “free” to “gratis” in the message subject:

${System.Text.RegularExpressions.Regex.Replace(MessageSubject, 'free', 'gratis')}