Post Data Null - AngularJS

app.config(function($httpProvider){

    $httpProvider.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded;charset=utf-8';

    var param = function(obj){

        var query = '', name, value, fullSubName, subName, subValue, innerObj, i;

        for(name in obj){

            value = obj[name];

            if(value instanceof Array){
                for(i=0; i<value.length; ++i){
                    subValue = value[i];
                    fullSubName = name + '[' + i + ']';
                    innerObj = {};
                    innerObj[fullSubName] = subValue;
                    query += param(innerObj) + '&';
                }
            }
            else if(value instanceof Object){
                for(subName in value){
                    subValue = value[subName];
                    fullSubName = name + '[' + subName + ']';
                    innerObj = {};
                    innerObj[fullSubName] = subValue;
                    query += param(innerObj) + '&';
                }
            }
            else if(value !== undefined && value !== null)
                query += encodeURIComponent(name) + '=' + encodeURIComponent(value) + '&';
            }

            return query.length ? query.substr(0, query.length - 1) : query;

        };

    $httpProvider.defaults.transformRequest = [function(data){
        return angular.isObject(data) && String(data) !== '[object File]' ? param(data) : data;
    }];

});