Got undefined input value in Ionic

i just wana get my input value in controller. But i always got an 'undefined' in web page.

This is my HTML code.

<div class="list">
        <label class="item item-input">
            <input id="FirstName" type="text" placeholder="* First Name" data-ng-model="Info.FirstName" />
        </label>
    </div>

And javascript.

 $scope.Info = {};

 $scope.Next = function () {

        switch (pageno) {
            case 1:
                alert($scope.Info.FirstName);
                break;
            case 2:
                alert($scope.Info.FirstName);
                break;
        };
}

when I click the button Next() will run and alert 'undefined'. It's a very simple function. I think is because I use ionic framework.

Are you trying to achieve this ??

HTML

<!DOCTYPE html>
<html ng-app="plunker">
  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.3.x" src="https://code.angularjs.org/1.3.15/angular.js" data-semver="1.3.15"></script>
    <script src="app.js"></script>
  </head>
  <body ng-controller="MainCtrl">
    <div class="list">
        <label class="item item-input">
            <input id="FirstName" type="text" placeholder="* First Name" ng-model="Info.FirstName" />
        </label>
        <button ng-click="Next(Info)"> Next </button>
        {{value}}
    </div>
  </body>
</html>

Controller

var app = angular.module('plunker', []);

app.controller('MainCtrl', function($scope) {

  $scope.Next = function (infodata) {
  $scope.value=infodata;      

};

});

Plnkr : http://plnkr.co/edit/X74FejDWVpxDRCB4v63n?p=preview