[javascript] Passing Javascript variable to <a href >

JAVASCRIPT CODE:

<script>

    function getUrlVars()
{
    var vars = [], hash;
    var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
    for(var i = 0; i < hashes.length; i++)
    {
        hash = hashes[i].split('=');
        vars.push(hash[0]);
        vars[hash[0]] = hash[1];
    }
    return vars;
}

var user = getUrlVars()["user"];
var pass = getUrlVars()["pass"];
var sub  = getUrlVars()["sub"];
</script>

<script>
    var myApp = angular.module('myApp',[]);

myApp.controller('dropdownCtrl', ['$scope','$window','$http', function($scope, $window, $http) {

 $http.get('http://dummy.com/app/chapter.php?user='+user+'&pass='+pass)

     .then(function (response) {$scope.names = response.data.admin;});
    $scope.names = [];

        $http.get('http://dummy.com/app/chapter.php?user='+user+'&pass='+pass+'&sub='+sub)

            .then(function (response) {$scope.chapter = response.data.chp;});
           $scope.chapter = [];

};


}]);
    </script>

HTML:

<div ng-controller="dropdownCtrl">
<div ng-repeat="a in chapter">
<a href="topic.html?ch={{a.chapter}}" onClick="location.href=this.href+'&user='+user+'&pass='+pass+'&sub='+sub;return false;">{{a.chapter}}</a>
</div>