how to use if else condition in jsx?

Question

class Wrapper extends React.Component {
  content() {
    if (this.props.isLoading) {
      return (
        <Layout>
            <Loader />
        </Layout>
      );
    } else if (this.props.isError) {
      return (
        <Layout>
          <Error errorMsg={this.props.error} />
        </Layout>
      );
    } else {
      return (
        <Layout>
            {this.props.isSuccess ? <h1>success</h1> : <h1>some failure</h1>}
        </Layout>
      );
    }
  }

  render() {
    return this.content();
  }
}

export default Wrapper;

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>

i have the above code , here i am using layout in every condition , actual <Layout> component is really heavy , so i want to use layout only once and trying to rewrite the code something like the below code. but its not rendering anything except layout.

class Wrapper extends React.Component {
  content() {
  return (
        <Layout>
        {(()=>{
        if (this.props.isLoading) {
             <Loader />
           }else if(this.props.isError){
        
              <Error errorMsg={this.props.error} />
              
                }else if(this.props.isSuccess){
              
               <h1>success</h1>
               
              }
              
        })()}
            
        </Layout>
      );
  }

  render() {
    return this.content();
  }
}

export default Wrapper;

syberen · Accepted Answer · 2018-04-02 19:14:26Z

2

How about something like this?

class Wrapper extends React.Component {
    render() {
        return (
            <Layout>
                {this.props.loading &&
                    <Loader />
                }
                {this.props.error &&
                    <Error errorMsg={this.props.error} />
                }
                {this.props.succes &&
                    <h1>success</h1>
                }
            </Layout>
        );
    }
}

export default Wrapper;

answered Apr 2, 2018 at 19:14

syberen

6791 gold badge6 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Mayank Shukla · Accepted Answer · 2018-04-02 19:19:23Z

Because you forgot to return the elements, by default function returns undefined. You defined a iife that will not return the result automatically, you need to do that.

Write it like this:

{(()=>{
    if (this.props.isLoading) {
        return <Loader />
    }else if(this.props.isError){
        return <Error errorMsg={this.props.error} />
    }else if(this.props.isSuccess){  
        return <h1>success</h1>   
    }

})()}

Consider this example to make the picture more clear, in this case renderElement function will return undefined, and nothing will get rendered.

render(){
    return (
        <div>
            {this.renderElement()}
        </div>
    )
}


// it will not return anything    
renderElement(){
    if (this.props.isLoading) {
        <Loader />
    }else if(this.props.isError){
        <Error errorMsg={this.props.error} />
    }else if(this.props.isSuccess){  
        <h1>success</h1>   
    }
}

IP_ · Accepted Answer · 2018-04-03 00:12:23Z

1

class Wrapper extends React.Component {

  render() {
   let content, message;

   this.props.error ? message = <Error errorMsg={this.props.error}> : null
   this.props.success ? message =  <h1>success</h1> : null
   this.props.isLoading ? content = <Loader/> : content = message

   return (
      <Layout>
         {content}
      </Layout>
    )}
}

export default Wrapper;

answered Apr 3, 2018 at 0:12

IP_

6955 silver badges19 bronze badges

Collectives™ on Stack Overflow

how to use if else condition in jsx?

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related