---
id: w3css-filters
title: "W3CSS Filters"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["filter tables", "filter lists", "W3.CSS 필터"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.85
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["w3css", "css-framework", "w3schools", "filter", "search"]
raw_sources: ["https://www.w3schools.com/w3css/w3css_filters.asp"]
applied_in: []
github_commit: ""
---

# [[W3CSS Filters]]

## 🎯 한 줄 통찰 (One-line insight)
Filtering, like tabs/pagination/slideshows before it, has NO dedicated W3.CSS filter class — the source explicitly frames this chapter as "with a little bit of JavaScript, ALL components in W3.CSS can be filtered," positioning filtering not as a component but as a general JS TECHNIQUE (matching input text against element content, toggling `display`) applicable to any existing structure — tables, lists, or dropdowns alike. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Universal applicability** — the same filter technique works on tables, unordered lists, and dropdown menus without any component-specific markup. [S1]
- **Core mechanism** — a text input's `oninput`/`onkeyup` event reads its value, then loops over target rows/items, hiding (`display:none`) any whose text content doesn't match. [S1]
- **No new CSS classes introduced** — this chapter teaches a JS PATTERN layered on top of previously covered structural classes (`w3-table`, `w3-ul`, `w3-dropdown-*`), not a new component. [S1]

## 📖 세부 내용 (Details)
- Filter Tables — an input filters visible `<table>` rows by matching against row text, hiding non-matches. [S1]
- Filter Lists — the same input-driven filtering pattern applied to `w3-ul` list items instead of table rows. [S1]
- Filter Dropdowns — demonstrated combined with both `w3-dropdown-hover` and `w3-dropdown-click` variants from the earlier Dropdowns chapter. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- 현재까지 발견된 모순 사항 없음 (No contradictions found in available sources).

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 테이블/리스트/드롭다운 어디에나 동일한 필터링 로직을 이식할 수 있다는 범용성이 실전 검색 UI 구현의 핵심 활용 사례다. [S1]

## 💻 코드 패턴 (Code patterns)
General-purpose filter pattern applicable to tables, lists, or dropdowns alike (conceptual JS pattern):
```javascript
function myFunction() {
  var input, filter, elements, i, txtValue;
  input = document.getElementById("myInput");
  filter = input.value.toUpperCase();
  elements = document.getElementsByTagName("li"); // or "tr" for tables
  for (i = 0; i < elements.length; i++) {
    txtValue = elements[i].textContent || elements[i].innerText;
    elements[i].style.display = txtValue.toUpperCase().indexOf(filter) > -1 ? "" : "none";
  }
}
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.85
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[W3.CSS Tutorial]]
- **관련 개념:** [[W3CSS Code]], [[W3CSS Tables]], [[W3CSS Lists]], [[W3CSS Dropdowns]], [[W3CSS Trends]]
- **참조 맥락:** 기존 구조 클래스 위에 얹는 JS 패턴 챕터 — 웹디자인 트렌드(Trends) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — W3.CSS Filters — https://www.w3schools.com/w3css/w3css_filters.asp

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "W3.CSS Filters" page (Astra wiki-curation, P-Reinforce v3.1 format).
