title: ng-bootstrap example calling method from component
body: <p>angular2 <a href="https://ng-bootstrap.github.io/#/components/dropdown" rel="noreferrer">ng-bootstrap drop down</a> dropdown component</p>
  
  <p>Can some one help me to find out how can i bind angular2 component with dropdown and call open or close method..</p>
  
  <p>they don't have much documentation.</p>