Allow slash in ng-pattern regex.

Should be straightforward enough. Trying to allow slash in my numeric only ng pattern for form field (expiration date).

HTML:

              <input type="text" id="expiration-date" name="expirationDate"
                data-ng-model="register.expirationDate"
                data-ng-pattern="/^[0-9]+$/"
                data-ng-minlength="7"
                maxlength="7"
                placeholder="MM/YYYY"
                data-ui-mask="99/9999"
                data-ng-required="true">

      

        
        
        
      

    

Attempting to resolve the forward slash in the model, otherwise the model will never update as it only accepts numbers. I have very little knowledge with regex.