var app = angular.module("sampleApp", []);
app.controller("demoCtrl", function () {
this.inputString = "javawebtutor";
this.reverseString = function () {
this.inputString = this.inputString.split("").reverse().join("");
}
});
<body ng-app="sampleApp">
<div ng-controller="demoCtrl as controller">
<h4>Controller without Scope</h4>
<div>
<span>
<button type="button"
ng-click="controller.reverseString()">Reverse</button>
</span>
<input ng-model="controller.inputString">
</div>
</div>
</body>