can i use if else in react jsx code example

Example 1: how to use if else inside jsx in react

renderElement(){
   if(this.state.value == 'news')
      return data;
   return null;
}

render() {
    return (   
        
            { this.renderElement() }
        
    )
}

Example 2: react native conditional rendering

function Mailbox(props) {
  const unreadMessages = props.unreadMessages;
  return (
    

      
Hello!
      {unreadMessages.length > 0 &&
        

          You have {unreadMessages.length} unread messages.
        
      }
    
  );
}