HtxExtension
and override the functions Execute and optionally ExecuteClose.
Execute and ExecuteClose is run on the same object, so it’s safe to store values from Execute and use them in ExecuteClose.
The content parameter passed to ExecuteClose is the parsed content from between the opening and the closing tag.
The name of the function will be as defined in the HtxExtension-attribute placed on the class.
See this example from the <z:sendmail
-function: