2nd/10_Wiki/Topics/Domain_Programming/Topic_CSharp/CSharp_Arrays.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
csharp-arrays	C# Arrays	Programming_Language	draft	conceptual		array declaration C# new keyword arrays C# 배열		B	0.84	2026-07-04	2026-07-04			csharp programming-language w3schools arrays	https://www.w3schools.com/cs/cs_arrays.php

CSharp Arrays

🎯 한 줄 통찰 (One-line insight)

C#'s array declaration puts the brackets right after the TYPE (string[] cars;), not after the variable name like C's char cars[4]; — a real syntactic divergence hiding under superficial similarity, and the tutorial explicitly documents FOUR equivalent ways to construct the same array (bare braces, new type[size], new type[size] {...}, new type[] {...}), while also stating a hard rule the C family never needed: if you declare an array first and assign its values LATER (in a separate statement), the new keyword becomes MANDATORY — omitting it is a compile error, unlike C where separate declaration and initialization of an array is simply not possible with a brace list at all. [S1]

🧠 핵심 개념 (Core concepts)

• Declaration syntax — type[] variableName; — brackets attach to the TYPE, not the variable name (contrast with C's type variableName[size];). [S1]
• Array literal — string[] cars = {"Volvo", "BMW", "Ford", "Mazda"}; — values in a comma-separated, brace-wrapped list. [S1]
• Index access, 0-based — cars[0] is the first element, same convention as every prior language in this series. [S1]
• Mutable elements — cars[0] = "Opel"; overwrites an existing element directly. [S1]
• .Length property — no parentheses, matching the string .Length property's design (property, not method). [S1]
• Four equivalent construction forms: new string[4] (empty, size 4), new string[4] {...} (size + values), new string[] {...} (values, size inferred), and bare {...} (values, size inferred, no new). [S1]
• new becomes mandatory when assigning after declaration — string[] cars; cars = new string[] {"Volvo", "BMW", "Ford"}; works, but cars = {"Volvo", "BMW", "Ford"}; (without new) is a compile error. [S1]

📖 세부 내용 (Details)

• Access: string[] cars = {"Volvo", "BMW", "Ford", "Mazda"}; Console.WriteLine(cars[0]); // Volvo. [S1]
• Modify: cars[0] = "Opel"; Console.WriteLine(cars[0]); // Opel. [S1]
• Length: Console.WriteLine(cars.Length); // 4. [S1]

⚖️ 모순 및 업데이트 (Contradictions & updates)

• 대괄호가 변수명이 아니라 타입에 붙음: C의 배열 선언은 char cars[4];처럼 대괄호가 변수명 뒤에 붙었지만, C#은 string[] cars;처럼 타입 바로 뒤에 대괄호가 붙는다는 점이 확인됨 — 표면적으로 비슷해 보이지만 실제 문법 위치가 다름. [S1]
• 선언 후 대입 시 new가 필수가 됨: 선언과 초기화를 분리할 경우(string[] cars; 이후 cars = {...};) 중괄호만으로는 컴파일 에러가 나고 반드시 new string[] {...}처럼 new를 붙여야 한다는 규칙이 확인됨 — C는애초에 배열을 선언 후 별도 문장에서 중괄호 리스트로 재할당하는 것 자체가 불가능하므로 C에는 없던 규칙. [S1]

🛠️ 적용 사례 (Applied in summary)

자동차 이름 배열을 선언하고, 첫 원소를 읽고 바꾸고, 길이를 확인하는 기본 흐름이 원문에서 직접 실전 활용 사례로 제시됨. [S1]

💻 코드 패턴 (Code patterns)

Four equivalent array construction forms, and the mandatory new on later assignment (C#):

string[] cars1 = new string[4];                              // empty, size 4
string[] cars2 = new string[4] {"Volvo", "BMW", "Ford", "Mazda"};
string[] cars3 = new string[] {"Volvo", "BMW", "Ford", "Mazda"};
string[] cars4 = {"Volvo", "BMW", "Ford", "Mazda"};           // no `new` needed here

string[] cars5;
cars5 = new string[] {"Volvo", "BMW", "Ford"};  // new REQUIRED when assigned separately
// cars5 = {"Volvo", "BMW", "Ford"};            // error without new

✅ 검증 상태 및 신뢰도

• 상태: draft
• 검증 단계: conceptual
• 출처 신뢰도: B (W3Schools — widely used educational reference, not a primary standards body)
• 신뢰 점수: 0.84
• 중복 검사 결과: 신규 생성 (New discovery)

🔗 지식 그래프 (Knowledge Graph)

• 상위/루트: C# Tutorial
• 관련 개념: CSharp Break, CSharp Arrays Loop, C Arrays, CPP Arrays
• 참조 맥락: Arrays 섹션 — Loop Through Arrays 챕터로 이어짐.

📚 출처 (Sources)

• [S1] W3Schools — C# Arrays — https://www.w3schools.com/cs/cs_arrays.php

📝 변경 이력 (Change history)

• 2026-07-04: Initial draft synthesized from the W3Schools "C# Arrays" page (Astra wiki-curation, P-Reinforce v3.1 format).