using ternary operator with two map

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I'm trying to learn react by coding, here i have come up with this code which works ! but only i need to know how to use if else or maybe ternary operator here. What i want to achieve is this: when user comes to the page this is already there :

{sisalto.map(({ avain, value }, index) => ( 
    <div>
        <div>
            <IndexBox y={avain} />
        </div>
        <div>
            <ValueBox value={value} />
        </div>
    </div>
))}

and when user writes something on input then this comes instead of the first one:

{searchResults.map(({ avain, value }, index) => ( 
    <div>
        <div>
            <IndexBox y={avain} />
        </div>
        <div>
            <ValueBox value={value} />
        </div>
    </div>
))}

my code :

function App() {
  const [data, setData] = useState([])
  const [searchResults, setSearchResults] = useState([])
  const [searchTerm, setSearchTerm] = useState('')
  const [sisalto, setSisalto] = useState([])

  const fetchData = () => {
    let corsAnywhere = 'https://cors-anywhere.herokuapp.com/'
    let something = 'http://ksngfr.com/something.txt'
    fetch(corsAnywhere + something)
      .then(response => response.text())
      .then(result => {
        const theDataArr = result.replace(/\n/g, ' ')
        const f = theDataArr.split(' ')
        setData(f)
      })
  }

  useEffect(() => {
    fetchData()
  }, [searchTerm])

  useEffect(() => {
    const mappedResult = data.map(d => {
      var propertyK = d.split(':')[0]
      var propertyv = d.split(':')[1]
      return {
        avain: propertyK,
        value: propertyv
      }
    })
    setSisalto(mappedResult)

    const results = mappedResult.filter(each => each.avain === searchTerm)
    setSearchResults(results)
  }, [data, searchTerm])
  console.log(sisalto)

  return (
    <div>
      <header>
        <div>
          <h1>something</h1>
          <input
            type="text"
            value={searchTerm}
            placeholder="Search..."
            onChange={e => setSearchTerm(e.target.value)}
          />
        </div>
      </header>
      <div>
        {searchResults.map(({ avain, value }, index) => (
          <div>
            <div>
              <IndexBox y={avain} />
            </div>
            <div>
              <ValueBox value={value} />
            </div>
          </div>
        ))}
      </div>
    </div>
  )
}

export default App

data i'm fetching :

/* ------------------------

    2005-07-09 03:05
    1:74539
    2:29734
    3:95426
    4:35489

------------------------ */
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1 Answers

You can use Ternary Operator like this

<div>
  {
     isTrue 
       ? (<div>YEP</div>) 
       : (<div>NO</div>)
  }
</div>

Now you can use React.Fragment to achieve your goal like this -

<div>
  {
     isTrue 
       ? (<React.Fragment>{/* map */}</React.Fragment>) 
       : (<React.Fragment>{/* map */}</React.Fragment>)
  }
</div>

// React.Fragment shorthand
<div>
  {
     isTrue 
       ? (<>{/* map */}</>) 
       : (<>{/* map */}</>)
  }
</div>

If you don't want anyting in else statement just let it be null like this

{ isTrue ? <>YEP</> : null }
user_66367620
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