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Updated: 2026年5月31日
Dom Create Element
Original task (JA): 新しい要素を作成
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Conclusion
Dom Create Element — free browser-based JavaScript (DOM) practice
Why it matters in real projects
createElementで要素を作り、appendChildで追加します。 Similar patterns appear daily in code review and production UI work.Step-by-step workflow
1. Read the guide and understand the goal of "Dom Create Element" 2. Review the JavaScript (DOM) editor pane and start from the starter code 3. Open hints if stuck; compare your diff with the sample solution 4. Click Run and inspect preview/console output 5. Auto-check looks for output containing: 新規. 6. After success, continue with adjacent exercises in the same categoryCore concept explained
createElementで要素を作り、appendChildで追加します。Technical focus
Key JavaScript APIs: document.createElement, document.getElementById.Hint before you peek at the solution
document.createElement, appendChildSample solution walkthrough
JavaScript APIs used: document.createElement, document.getElementById. Verify spelling and async/await usage. Explanation: createElementで要素を作り、appendChildで追加します。 Hint recap: document.createElement, appendChildSolution code
📝 Sample code
const p = document.createElement('p');
p.textContent = '新規';
document.getElementById('container')?.appendChild(p);Common mistakes for this exact task
・Skipping the hint: document.createElement, appendChild ・getElementById returns null if the id string differs by even one characterTroubleshooting
Q: Preview does not change after Run A: Ensure you edited the JavaScript (DOM) pane and clicked Run. Q: Looks correct but check fails A: Auto-check looks for output containing: 新規. Look for typos, full-width spaces, or unclosed tags. Q: Console shows errors A: Open DevTools Console and fix bracket/quote mismatches at the reported line. Q: Hard to type on mobile A: Use landscape mode or continue on desktop—the same URL keeps progress in localStorage.Interview / portfolio tips
・Explain the techniques in "Dom Create Element" in your own words within 30 seconds ・Practice walking through each line of the sample solution on a whiteboard ・Connect this task to a real component you would ship ・Mention responsive or accessibility trade-offs ・Describe when you use: document.createElement, document.getElementByIdWhat to do after you pass
Move to the next exercise in the dom track, then continue the learning roadmap at /en/learning/js-basic/.Keywords
Free hands-on exercise covering 新しい要素を作成, dom, 初級, document.createElement, document.getElementById, dom create element—search-friendly guide for Dom Create Element.🧪 Try it here — safe to break things
Use the editor below to write code and preview instantly.
Jump to editor■ Exercise task
pタグを作り、テキストを「新規」にして、idが「container」の要素の子として追加してください。
Hint if stuck
document.createElement, appendChild