Mengindeks tatasusunan JSON bersarang

Question

Saya mempunyai contoh JSON berikut di mana "results" 下有一个数组，其中包含两个对象。它可以在 “results” mengandungi ratusan objek dengan kunci yang sama dan nilai berbeza di bawah tatasusunan.

Saya tiada kebenaran untuk menukar fail JSON ini.

{
  "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..."
    }
  ]
}

Saya mempunyai kod berikut untuk mendapatkan dan memaparkan nilai yang diperlukan untuk setiap kunci dalam tatasusunan seperti yang ditunjukkan di bawah:

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>

Semuanya baik kecuali satu perkara.

Seperti yang anda lihat, json saya mempunyai tatasusunan bersarang di bawah "agencies" yang mengandungi berbilang objek.

Saya cuba menggunakan pengindeksan untuk mendapatkan setiap nilai di bawah raw_name untuk setiap objek.

Kalau saya guna + myArr.results[i].agencies[0].raw_name 它适用于单个对象。可能是 [0] 或 [1].

Apabila saya cuba mendapatkan nilai kedua seperti + myArr.results[i].agencies[0].raw_name + " - " + myArr.results[i].agencies[1].raw_name ia memecahkan keseluruhan kod saya tidak mendapat balasan

Ada idea apa yang saya buat salah?

Terima kasih!

Answer 1

Gunakan gelung bersarang untuk memproses semua badan. Anda boleh menggunakan map() 循环它们并返回名称数组，并使用 join() untuk menyambungkannya dengan pemisah.

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
";
  }