Anil Singh | Code-sample.com

The  Unmounting  is used when a component is removed from the DOM. React has only one built-in method that is called when a component is unmounted. 1.        componentWillUnmount The componentWillUnmount Method  - The componentWillUnmount() method is called when the component is removed from the DOM. Explore to Understand   -  React Lifecycle Components As an Example , // container class public   class   Container   extends   React . Component  {    constructor ( props ) {      super ( props );      this . state  = { show:   true };   }    deleteHeader  = ()  =>  {      this . setState ({ show:   false });   }    render () {      let   header ;   ...