React | Ex2

 let isLoggedIn=true;

// isLoggedIn=false;

let username = "Chandan";


class UserStatus extends React.Component {

  render() {

    return (

      <div>

        <button>Login</button>

        <h2> Hey, {username}!</h2>

      </div>

        )

  }

}


ReactDOM.render(

  <UserStatus />,

  document.getElementById('root')

);


------------------------------------------------------------------------------------------------

State and event handling

------------------------------------------------------------------------------------------------

class LikeCounter extends React.Component {

  state = {

    counter : 0

  }

  

  likeButtonHandler = () => {

    this.setState({ counter: this.state.counter + 1 });

  } 

  

  render() {

    console.log('render function is being called with state', this.state.counter);

    

    return (

      <div>

        <button onClick={this.likeButtonHandler}> ❤️ </button>

        <h2> Likes {this.state.counter} </h2>

      </div>

        )

  }

}


ReactDOM.render(

  <LikeCounter />,

  document.getElementById('root')

);


----------------------------------------------------------------------------------------------------------------------

sugar cart state handling

----------------------------------------------------------------------------------------------------------------------

 class Cart extends React.Component {

  state = {

    cartCounter : 0

  }

    addToCart = () => {


    this.setState({ cartCounter: this.state.cartCounter + 1 });

    console.log('add console');

    console.log(this.state.cartCounter);



  } 

  removeFromcart = () => {


    this.setState({ cartCounter: this.state.cartCounter - 1 });

    console.log('remove console');

    console.log(this.state.cartCounter);

    if(this.state.cartCounter<2){

       console.log('Empty Cart');

    }


  } 

  

   render() {

      return (

      <div>

        <h1>Sugar</h1>

        <button onClick={this.addToCart}> Add to Cart </button>

        <button onClick={this.removeFromcart}> Remove from Cart </button>

        <h2>Cart Status: {this.state.cartCounter}</h2>


      </div>

        )

  }

   }



ReactDOM.render(

  <Cart />,

  document.getElementById('root')

);



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