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javascript - Console log of array is empty

I have these two code examples:

no1

const r = new Array();

for (i = 0; i < 5; i++) {
  const vari = 'print';
  r.push(vari);
}

console.log(r);

console log of this is [ 'print', 'print', 'print', 'print', 'print' ]

no2(using cheerio for scraping)

const sqft = new Array();
      for (k = 0; k < links.length; k++) {
        request(`${links[k]}`, (error, response, html) => {
          const $ = cheerio.load(html);
          const pr = $('div[class="df2  "]').first().text();
          sqft.push(pr);
        });
      }
console.log(sqft);

Links are pushed in request before this. Now when I console.log(sqft) I get []. If I console.log it inside for loop it will show data. Is it the difference between no1 and no2 or cheerio is making a problem? Thanks!


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1 Answer

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by (71.8m points)

It looks like you have asynchronous operation. So we need to use async and await keywords to make execution synchronous:

async function yourFunction() {
    const sqft = new Array();
    for (k = 0; k < links.length; k++) {
        // here we are waiting for the promise to be resolved
        let res = await request();
        const $ = cheerio.load(res.html);
        const pr = $('div[class="df2  "]').first().text();
        sqft.push(pr);
    }
}

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