javascript - Bootstrap validator regex pattern not working -

i trying simple regex in code

<textarea pattern="[a-z]{1,15}$" class="form-control" rows="4" id="test" maxlength="500" required></textarea> 

i have tried following example

<input type="text" pattern="^[_a-z0-9]{1,}$" maxlength="15" class="form-control" id="inputtwitter" placeholder="1000hz" required> 

http://1000hz.github.io/bootstrap-validator/#validator-examples

the required field validations seem working patterns don't seem working. eventual goal simple alpha numeric/text/punctuation validation working mentioned here https://stackoverflow.com/a/7233549/544982 want able use regex [a-za-z0-9 _.,!"'/$]*

also if add data-toggle tag on form field, submit button showing disabled still allows me submit. tag doesn't seem helping.

<form data-toggle="validator">