Indexation des tableaux JSON imbriqués

Question

J'ai l'exemple JSON suivant où "results" 下有一个数组，其中包含两个对象。它可以在 “results” contient des centaines d'objets avec la même clé et des valeurs différentes sous le tableau.

Je n'ai pas l'autorisation de modifier ce fichier JSON.

{
  "results": [
    {
      "title": "Information Collection Requests; Direct Loan Servicing-Regular; and Servicing Minor Program Loans",
      "type": "Notice",
      "abstract": "In accordance with the Paperwork Reduction Act (PRA) requirement, the Farm Service Agency (FSA) is requesting comments from all interested individuals and organizations on a revision of two currently approved information collection requests, Direct Loan Servicing--Regular and Servicing Minor Program Loans, respectively. In the Direct Loan Servicing--Regular, the information is used to determine borrower compliance with loan agreements, assist the borrower in achieving business goals, and regular servicing of the loan account such as graduation, subordination, partial release, use of proceeds, and consent. In Servicing Minor Program Loans, the information collected is used to perform routine and special servicing actions for loans authorized and serviced under FSA's Minor Loan Program.",
      "document_number": "2023-05464",
      "html_url": "https://www.federalregister.gov/documents/2023/03/17/2023-05464/information-collection-requests-direct-loan-servicing-regular-and-servicing-minor-program-loans",
      "pdf_url": "https://www.govinfo.gov/content/pkg/FR-2023-03-17/pdf/2023-05464.pdf",
      "public_inspection_pdf_url": "https://public-inspection.federalregister.gov/2023-05464.pdf?1678970722",
      "publication_date": "2023-03-17",
      "agencies": [
        {
          "raw_name": "DEPARTMENT OF AGRICULTURE",
          "name": "Agriculture Department",
          "id": 12,
          "url": "https://www.federalregister.gov/agencies/agriculture-department",
          "json_url": "https://www.federalregister.gov/api/v1/agencies/12",
          "parent_id": null,
          "slug": "agriculture-department"
        },
        {
          "raw_name": "Farm Service Agency",
          "name": "Farm Service Agency",
          "id": 157,
          "url": "https://www.federalregister.gov/agencies/farm-service-agency",
          "json_url": "https://www.federalregister.gov/api/v1/agencies/157",
          "parent_id": 12,
          "slug": "farm-service-agency"
        }
      ],
      "excerpts": "In accordance with the Paperwork Reduction Act (PRA) requirement, the Farm Service Agency (FSA) is requesting comments from all interested individuals and organizations on a revision of two currently approved information collection requests, Direct..."
    },
    {
      "title": "Notice of Funding Opportunity for the Socially Disadvantaged Groups Grant for Fiscal Year 2023",
      "type": "Notice",
      "abstract": "This notice announces that the Rural Business-Cooperative Service (RBCS, Agency), a Rural Development (RD) agency of the United States Department of Agriculture (USDA), invites applications for grants under the Socially Disadvantaged Groups Grant (SDGG) program for Fiscal Year (FY) 2023. This notice is being issued to allow applicants sufficient time to leverage financing, prepare and submit their applications, and give the Agency time to process applications within FY 2023. A total of ,000,000 in grant funding will be available for FY 2023. Successful applications will be selected by the Agency for funding and subsequently awarded to the extent that funding may ultimately be made available through appropriations. All applicants are responsible for any expenses incurred in developing and submitting their applications.",
      "document_number": "2023-05441",
      "html_url": "https://www.federalregister.gov/documents/2023/03/17/2023-05441/notice-of-funding-opportunity-for-the-socially-disadvantaged-groups-grant-for-fiscal-year-2023",
      "pdf_url": "https://www.govinfo.gov/content/pkg/FR-2023-03-17/pdf/2023-05441.pdf",
      "public_inspection_pdf_url": "https://public-inspection.federalregister.gov/2023-05441.pdf?1678970718",
      "publication_date": "2023-03-17",
      "agencies": [
        {
          "raw_name": "DEPARTMENT OF AGRICULTURE",
          "name": "Agriculture Department",
          "id": 12,
          "url": "https://www.federalregister.gov/agencies/agriculture-department",
          "json_url": "https://www.federalregister.gov/api/v1/agencies/12",
          "parent_id": null,
          "slug": "agriculture-department"
        },
        {
          "raw_name": "Rural Business-Cooperative Service",
          "name": "Rural Business-Cooperative Service",
          "id": 456,
          "url": "https://www.federalregister.gov/agencies/rural-business-cooperative-service",
          "json_url": "https://www.federalregister.gov/api/v1/agencies/456",
          "parent_id": 12,
          "slug": "rural-business-cooperative-service"
        }
      ],
      "excerpts": "This notice announces that the Rural Business-Cooperative Service (RBCS, Agency), a Rural Development (RD) agency of the United States Department of Agriculture (USDA), invites applications for grants under the Socially Disadvantaged Groups Grant..."
    }
  ]
}

J'ai le code suivant pour obtenir et afficher la valeur requise pour chaque clé du tableau, comme indiqué ci-dessous :

const xmlhttp = new XMLHttpRequest();
xmlhttp.onload = function() {
  const myArr = JSON.parse(this.responseText);

  let text = "";
  for (let i in myArr.results) {
    text += "<div class='fed-reg-container'><h2 class='title'>" + myArr.results[i].title + "</h2><p>" + myArr.results[i].type + "</p><p>" + myArr.results[i].agencies[0].raw_name + " Document # " + myArr.results[i].document_number + "</p><p>Posted on: " + myArr.results[i].publication_date + "</p><p>" + myArr.results[i].abstract + "</p><a class='fed-reg-button' href='" + myArr.results[i].html_url + "'>Read More</a></div>";
  }
  text += "";
  document.getElementById("demo").innerHTML = text;
};
xmlhttp.open(
  "GET",
  "https://www.federalregister.gov/api/v1/documents.json?conditions%5Bagencies%5D%5B%5D=agriculture-department&conditions%5Bagencies%5D%5B%5D=federal-highway-administration&conditions%5Bagencies%5D%5B%5D=fish-and-wildlife-service&conditions%5Bagencies%5D%5B%5D=forest-service&conditions%5Bagencies%5D%5B%5D=interior-department&conditions%5Bagencies%5D%5B%5D=international-boundary-and-water-commission-united-states-and-mexico&conditions%5Bagencies%5D%5B%5D=land-management-bureau&conditions%5Bagencies%5D%5B%5D=national-highway-traffic-safety-administration&conditions%5Bagencies%5D%5B%5D=national-park-service&conditions%5Bagencies%5D%5B%5D=reclamation-bureau&conditions%5Bagencies%5D%5B%5D=environmental-protection-agency&conditions%5Bagencies%5D%5B%5D=council-on-environmental-quality&conditions%5Bagencies%5D%5B%5D=safety-and-environmental-enforcement-bureau&conditions%5Bagencies%5D%5B%5D=environment-office-energy-department&conditions%5Bcomment_date%5D%5Bgte%5D=05%2F01%2F2023&conditions%5Bcomment_date%5D%5Blte%5D=01%2F01%2F2050&conditions%5Bterm%5D=arizona&conditions%5Btype%5D%5B%5D=RULE&conditions%5Btype%5D%5B%5D=PRORULE&conditions%5Btype%5D%5B%5D=NOTICE",
  true
);
xmlhttp.send();

.fed-reg-container {
  background-color: black;
  color: white;
  padding: 20px;
  margin: 20px 0;
}

.title {
  color: #fcb900;
}

.fed-reg-button {
  background-color: #fcb900;
  color: black;
  padding: 10px;
  display: block;
  max-width: 100px;
  text-align: center;
  font-weight: 600;
  text-decoration: none;
}

<!DOCTYPE html>
<html>

<body>
  <p id="demo"></p>

</body>

</html>

Tout va bien sauf une chose.

Comme vous pouvez le voir, mon json a un tableau imbriqué sous "agencies" qui contient plusieurs objets.

J'essaie d'utiliser l'indexation pour obtenir chaque valeur sous raw_name pour chaque objet.

Si j'utilise + myArr.results[i].agencies[0].raw_name 它适用于单个对象。可能是 [0] 或 [1].

Quand j'essaie d'obtenir la deuxième valeur comme + myArr.results[i].agencies[0].raw_name + " - " + myArr.results[i].agencies[1].raw_name, cela casse tout le code, je n'obtiens rien en retour

.

Une idée de ce que j'ai fait de mal ?

Merci !

Answer 1

Utilisez des boucles imbriquées pour traiter tous les corps. Vous pouvez utiliser map() 循环它们并返回名称数组，并使用 join() pour les connecter avec des séparateurs.

for (let i in myArr.results) {
    let agencies = myArr.results[i].agencies.map(a => a.raw_name).join(', ');
    text += "
" + myArr.results[i].title + "
" + myArr.results[i].type + "
" + agencies + " Document # " + myArr.results[i].document_number + "
Posted on: " + myArr.results[i].publication_date + "
" + myArr.results[i].abstract + "
Read More
";
  }