How to get use ng-pattern

I have a simple text input in which I only want to allow floats and ints (watch out: jade)

input.form-control(type="text", ng-model='usd', ng-pattern="nums",ng-change='convert_to_btc()', placeholder="USD")

However it doesn't work, I can always insert any character in the input (do I need to do more in order to display something? e.g. a red border if it's incorrrect? or should then just those characters not even be able to be entered?) The pattern is a regex and thus not a string, so that should be fine???

Here's the controller:

app.controller("AppCtrl", function AppCtrl($scope, $http, $interval ) {
    //lots of other stuff
    $scope.nums = /^\-?\d+((\.|\,)\d+)?$/; //note no string, it's a  regex
}

This is the generated HTML. Could this be the problem? The generated HTML actually has a string, not a regex!?

<input type="text" ng-model="usd" ng-pattern="/^\-?\d+((\.|\,)\d+)?$/" ng-change="convert_to_btc()" placeholder="USD" class="form-control ng-dirty ng-valid-parse ng-touched ng-invalid ng-invalid-pattern">

Solution

I hope this is what you are trying to do.

Please have a look at the below link

http://plnkr.co/edit/BGzLbQHy0ZtHYmom8xA3

<!DOCTYPE html>
<html ng-app="">

<head>
 <script data-require="[email protected]" src="https://code.angularjs.org/1.3.13/angular.js" data-semver="1.3.13">      
 </script>
  <style>
    .ng-invalid-pattern {
      border:1px solid #f00;
    }
  </style>
</head>

<body>
  <p>Hello</p>

  <form name='myform'>      
    <input type="text" name='ip' ng-model="usd" ng-pattern="/^\-?\d+((\.|\,)\d+)?$/" 
  ng-change="convert_to_btc()" placeholder="USD"/>
    <p ng-show='myform.ip.$invalid'>Error</p>
  </form>


  </body>

</html>