2nd/10_Wiki/Topic_JavaScript/JavaScript_JSON_Objects.md

id, title, category, status, verification_status, canonical_id, aliases, duplicate_of, source_trust_level, confidence_score, created_at, updated_at, review_reason, merge_history, tags, raw_sources, applied_in, github_commit

id	title	category	status	verification_status	canonical_id	aliases	duplicate_of	source_trust_level	confidence_score	created_at	updated_at	review_reason	merge_history	tags	raw_sources	applied_in	github_commit
json-objects	JSON Objects	Frontend	draft	conceptual		JSON objects JSON object literal access JSON object loop JSON object JSON dot bracket notation		B	0.88	2026-06-23	2026-06-23			javascript js web frontend w3schools json objects	https://www.w3schools.com/js/js_json_objects.asp

JSON Objects

🎯 한 줄 통찰 (One-line insight)

A JSON object literal is curly-brace text of key/value pairs; once parsed into a JavaScript object you read its members by dot or bracket notation and iterate them with a for-in loop — but the literal itself is a string format, not "a JSON object." [S1]

🧠 핵심 개념 (Core concepts)

• JSON object literals are surrounded by curly braces {} and contain key/value pairs. [S1]
• Keys and values rules — keys must be strings, and values must be a valid JSON data type. [S1]
• Terminology caution — it is a common mistake to call a JSON object literal "a JSON object." JSON cannot be an object; JSON is a string format. [S1]
• Two ways to obtain an object — write a JavaScript object directly from a literal, or parse a JSON string with JSON.parse(). [S1]
• Two ways to access members — dot notation (myObj.name) or bracket notation (myObj["name"]). [S1]
• Iterate with for-in — loop over keys, and access each value via myObj[x]. [S1]

🧩 추출된 패턴 (Extracted patterns)

• Literal → object — myObj = {...} or myObj = JSON.parse(myJSON). [S1]
• Dot vs bracket access — myObj.name equals myObj["name"]. [S1]
• For-in over keys — for (const x in myObj) yields keys; index with myObj[x] for values. [S1]

📖 세부 내용 (Details)

JSON object literals JSON object literals are surrounded by curly braces {}. JSON object literals contains key/value pairs. Keys must be strings, and values must be a valid JSON data type. It is a common mistake to call a JSON object literal "a JSON object." JSON cannot be an object. JSON is a string format. [S1]

This is a JSON string: [S1]

{"name":"John", "age":30, "car":null}

Creating a JavaScript object You can create a JavaScript object directly from a JSON object literal: [S1]

myObj = {"name":"John", "age":30, "car":null};

Normally you create a JavaScript object by parsing a JSON string: [S1]

myObj = JSON.parse(myJSON);

Accessing object values You can access object values by using dot (.) notation: [S1]

x = myObj.name;

You can also access object values by using bracket ([]) notation: [S1]

x = myObj["name"];

Looping an object You can loop through object properties with a for-in loop. Loop printing the keys: [S1]

const myJSON = '{"name":"John", "age":30, "car":null}';
const myObj = JSON.parse(myJSON);

let text = "";
for (const x in myObj) {
  text += x + ", ";
}

In a for-in loop, use the bracket notation to access the values: [S1]

const myJSON = '{"name":"John", "age":30, "car":null}';
const myObj = JSON.parse(myJSON);

let text = "";
for (const x in myObj) {
  text += myObj[x] + ", ";
}

🛠️ 적용 사례 (Applied in summary)

Applied examples on the page: build myObj from a literal and from JSON.parse(); read values via dot and bracket notation; and iterate with for-in (keys, then values via myObj[x]). No external project/commit applications found in the source.

💻 코드 패턴 (Code patterns)

Parse then access:

const myObj = JSON.parse('{"name":"John", "age":30, "car":null}');
x = myObj.name;       // dot notation
x = myObj["name"];    // bracket notation

Iterate values:

let text = "";
for (const x in myObj) {
  text += myObj[x] + ", ";
}

⚖️ 모순 및 업데이트 (Contradictions & updates)

No contradictions found in the source.

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual (실제 적용 사례 발견 시 applied/validated로 승격 가능)
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.88
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: JavaScript Tutorial
• 관련 개념: JavaScript JSON Arrays, JavaScript JSON Parse, JavaScript JSON Data Types, JavaScript JSON Syntax
• 참조 맥락: Referenced whenever reading or iterating the members of a parsed JSON object.

📚 출처 (Sources)

• [S1] W3Schools — JSON Objects — https://www.w3schools.com/js/js_json_objects.asp

📝 변경 이력 (Change history)

• 2026-06-23: Initial draft synthesized from the W3Schools "JSON Objects" page (Astra wiki-curation, P-Reinforce v3.1 format).