---
id: php-if-else
title: "PHP If Else"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["if statement", "PHP 조건문"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.9
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["php", "programming", "w3schools", "conditions", "if"]
raw_sources: ["https://www.w3schools.com/php/php_if_else.asp"]
applied_in: []
github_commit: ""
---

# [[PHP If Else]]

## 🎯 한 줄 통찰 (One-line insight)
PHP names four distinct conditional statement forms upfront (if / if-else / if-elseif-else / switch) as one family, framing them as increasingly powerful tools for the same underlying task — selecting which code runs — rather than teaching `if` in isolation. [S1]

## 🧠 핵심 개념 (Core concepts)
- **`if (condition) { ... }`** — runs a code block only when the condition is true. [S1]
- **Four conditional forms overview** — if, if...else, if...elseif...else, switch — each handles a different number of branches. [S1]
- **Braces required for blocks** — the code to run sits inside `{ }`. [S1]

## 📖 세부 내용 (Details)
- Literal comparison: `if (5 > 3) { echo "Have a good day!"; }`. [S1]
- Variable comparison: `$t = 14; if ($t < 20) { echo "Have a good day!"; }`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
소스에서 모순되는 정보는 발견되지 않음.

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 조건문 4종 세트의 첫 단계로, 비교 연산자(If Operators) 챕터로 바로 확장된다. [S1]

## 💻 코드 패턴 (Code patterns)
Basic if with a variable condition (PHP):
```php
$t = 14;
if ($t < 20) {
    echo "Have a good day!";
}
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.90
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[PHP Tutorial]]
- **관련 개념:** [[PHP Operators]], [[PHP If Operators]], [[PHP If Else If]], [[PHP Switch]]
- **참조 맥락:** 조건문의 출발점 — 비교/논리 연산자(If Operators) 챕터로 직접 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — PHP if Statements — https://www.w3schools.com/php/php_if_else.asp

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