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I have have the regular expression $scope.pa = /^([\w-~!@#\$]+)$/i which is working fine for my requirements. Now I want to restrict this regular expression so that it can allow only 0 to 15 characters. So I have changed it to $scope.pa = /^([\w-~!@#\$]+){0,15}$/i; but that 0 to 15 characters restriction is not working out. 

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title></title>
    <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.2/angular.min.js"></script>
</head>
<body ng-app="app">
    <div ng-controller="controllerName">
        <ng-form name="mailForm">
             Pname: <input type="text" ng-model="pname" name="pname" ng-pattern="pa" /><br />
            <span ng-show="mailForm.pname.$error.pattern" style="color:red">Please enter pname</span>


        </ng-form>
    </div>
    <script>
    var app = angular.module("app", []);
    app.controller('controllerName', ['$scope', function ($scope) {
         $scope.pname = "abcd267g";
           $scope.pa = /^([\w-~!@#\$]+)$/i;

          }]);
</script>
</body>
</html>
Madasu K
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1 Answers1

2

Now I want to restrict this regular expression so that it can allow only 0 to 15 characters.

To achieve this you should be applying range restriction on character class [ ] and not the group ( ).

Right now you have applied it to whole group /^([\w-~!@#\$]+){0,15}$/i which will repeat infinite characters 0 to 15 times. Which renders range restriction useless.

Thus, {0,15} should come after [\w-~!@#\$] and your regex will be:

/^([\w\-~!@#\$]{0,15})$/i;

Rahul
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