---
id: csharp-conditions
title: "C# If ... Else"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["if statement C#", "C# 조건문"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.83
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["csharp", "programming-language", "w3schools", "conditions", "if"]
raw_sources: ["https://www.w3schools.com/cs/cs_conditions.php"]
applied_in: []
github_commit: ""
---

# [[CSharp Conditions]]

## 🎯 한 줄 통찰 (One-line insight)
The `if (condition) { ... }` syntax is byte-identical to C/C++/Java, and the chapter's own explicit warning — "if is in lowercase letters; If or IF will generate an error" — is the same case-sensitivity rule already established in the Identifiers chapter, now applied to KEYWORDS rather than variable names, closing the loop on C#'s case-sensitivity being a blanket rule across the entire language (identifiers AND keywords), not just a variable-naming quirk. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Comparison conditions inherited from math** — `<`, `<=`, `>`, `>=`, `==`, `!=`, already covered in the Comparison Operators chapter, are the building blocks of every condition. [S1]
- **Four conditional constructs previewed** — `if` (execute if true), `else` (execute if false), `else if` (test a new condition if the first was false), `switch` (many alternative blocks). [S1]
- **`if` syntax**: `if (condition) { // code }` — code inside the braces runs only when `condition` evaluates to `True`. [S1]
- **Case-sensitivity applies to keywords, not just identifiers** — `If` or `IF` (capitalized) is a compile error; only lowercase `if` is valid. [S1]

## 📖 세부 내용 (Details)
- Literal condition: `if (20 > 18) { Console.WriteLine("20 is greater than 18"); }`. [S1]
- Variable condition: `int x = 20; int y = 18; if (x > y) { Console.WriteLine("x is greater than y"); }`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- **대소문자 구분이 키워드에도 적용됨을 명시적으로 확인**: Identifiers 챕터에서 변수명의 대소문자 구분(`myVar` vs `myvar`)을 배웠는데, 이번 챕터는 `if`라는 키워드 자체도 대문자로 쓰면(`If`, `IF`) 에러가 난다고 명시 — 대소문자 구분이 식별자뿐 아니라 언어 전체(키워드 포함)에 적용되는 규칙임이 확인됨. [S1]

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 리터럴 비교(20 > 18)와 변수 비교(x > y) 두 가지 if 예제가 원문에서 제시됨. [S1]

## 💻 코드 패턴 (Code patterns)
Basic if statement — lowercase `if` only (C#):
```csharp
int x = 20;
int y = 18;
if (x > y)
{
    Console.WriteLine("x is greater than y");
}
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.83
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[C# Tutorial]]
- **관련 개념:** [[CSharp Booleans]], [[CSharp Conditions Else]], [[CPP Conditions]]
- **참조 맥락:** Conditions 섹션 — The else Statement 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — C# If ... Else — https://www.w3schools.com/cs/cs_conditions.php

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "C# If ... Else" page (Astra wiki-curation, P-Reinforce v3.1 format).