add a new form when onclick event occurs in reactjs code example

Example 1: react button onclick

import React, { Component } from 'react';

class App extends Component {
  
  constructor(props) {
    super(props);
    this.sayHello = this.sayHello.bind(this);
  }

  sayHello() {
    alert('Hello!');
  }
  
  return (
    <button onClick={this.sayHello}>
      Click me!
    </button>
  );
}

export default App;

Example 2: react button onclick

import React from 'react';

function App() {

  function sayHello() {
    alert('Hello!');
  }
  
  return (
    <button onClick={sayHello}>
      Click me!
    </button>
  );
}

export default App;

Example 3: onclick re

handleClick(id) {

    this.setState({

        vote_status: !this.state.vote_status,

    })

    let vote_object = {
        voting_object: id,
        post_id: this.props.postId
    }
    this.props.submitvote(vote_object)

    //this.forceUpdate()
}

render() {

    console.log("getVoteStatus", this.props.getVoteStatus)

    let {contents, submitvote, postId, voted_id} = this.props

    return (

        <div className="txt_vote_bar_div" style={{
            color: voted_id === contents.post_poll_content_id ? 'white' : '#9da0a4',
            backgroundColor: this.state.vote_status ? '#0b97c4' : '#FFFFFF'
        }} id={contents.post_poll_content_id}>
            <p className="txt_vote_choice"
               style={{color: this.state.vote_status || voted_id === contents.post_poll_content_id ? '#FFFFFF' : '#6a6a6a'}}
               id={"id" + contents.post_poll_content_id}
               onClick={() => {
                   this.handleClick(contents.post_poll_content_id);

               }}> {contents.content} </p>
            <p className="txt_tot_votes"
               style={{color: this.state.vote_status || voted_id === contents.post_poll_content_id ? '#FFFFFF' : '#6a6a6a'}}> {contents.votes}%
                (Votes:)</p>
        </div>
    );
};

Example 4: handling event in jsx

//Event hadling in react
function ActionLink() {
  function handleClick(e) {
    e.preventDefault();
    console.log('The link was clicked.');
  }

  return (
    <a href="#" onClick={handleClick}>
      Click me
    </a>
  );
}