How to customize constraints in textbox

Hi everyone,

I haven't been able to fully understand how the custom constraints in textboxs work, in a past thread a fellow forum member explained to me how to validate an email you should put:

. But I did not understand how it works, I mean.........does the constraint have to start and end with the "/"? and how that validates de period (like in mail.com) because if you don't have the format [email protected] it doesn't appear valid.

So I was hoping you guys could help understand the syntax, particularly because I need to forbid the entering of "<" and ">" in a textbox, and I know I can just do:
Or something on the java end, but I would be a lot easier to include that constraint on the textbox in the zul.


Thank you so much in advance!

judacoor