Incrementing state value by one using React

Question

In React I am trying to make a button increment a value stored in state. However using the code below function my value is set undefined or NaN when using handleClick.

Answer 1

import React from 'react'

class App extends React.Component{
  constructor(){
    super()
    this.state = {
      count: 0
    }
    this.handleClick = this.handleClick.bind(this)
  }
  handleClick(){
    this.setState(prevState => {
      return {
        count: prevState.count + 1
      }
    })
  }
  render(){
    return(
      

        
{this.state.count}
        Change
      
    )
  }
}
export default App