Forms and input

Instant Validation Form for Course Registration

Complete a live-validation form for a course enrollment scenario: includes realistic content, actionable controls, clear status feedback, and responsive layouts across sizes.

Forms and inputInstant Validation FormHTMLCSSJavaScript
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<body data-aesthetic="magazine" data-composition="field-index">
  <main class="page">
    <header class="mast"><div><span class="eyebrow">magazine / Instant Validation Form / BEGINNER</span><h1>Instant Validation Form for Course Registration</h1><p class="intro">Complete a live-validation form for a course enrollment scenario: includes realistic content, actionable controls, clear status feedback, and responsive layouts across sizes.</p></div><span class="scenario">Course registration</span></header>
    <div class="composition-index"><section class="demo" aria-label="Course enrollment live validation form interactive area"><div class="workflow-session"><header class="session-command"><div><span class="eyebrow">Course enrollment SESSION</span><h2>Course Planning Timeline</h2></div><output id="workflowSessionClock">00:45</output><label>Round Duration<input id="workflowSessionLength" type="range" min="15" max="90" step="15" value="45"><span>sec</span></label><button id="workflowSessionToggle" class="action primary" type="button">Start course enrollment submission</button></header><div id="workflowSessionProgress" role="progressbar" aria-label="Course enrollment plan progress" aria-valuemin="0" aria-valuemax="100" aria-valuenow="0"><i></i></div><section id="workflowCore" class="workflow-core session-stage" data-session-phase="ready" tabindex="-1"><!-- 11DZ_CORE_START:forms-input-live-validation --><form id="demoForm" class="form-card form-mode-0 panel" novalidate><div class="form-heading"><span class="eyebrow">Fill in safely · MODE 1</span><h2>Instant Validation Form</h2><p class="muted">Field errors are explained in place and will not clear the entered content.</p></div><label class="field"><span>Name</span><input name="name" minlength="2" required autocomplete="name" aria-describedby="nameError"><small id="nameError"></small></label><label class="field"><span>Contact email</span><input name="email" type="email" required autocomplete="email" aria-describedby="emailError"><small id="emailError"></small></label><label class="field field-note"><span>Description</span><textarea name="note" rows="3" minlength="8" required aria-describedby="noteError"></textarea><small id="noteError"></small></label><button class="action primary" type="submit" data-core-bridge="forms-input-live-validation">Review and submit</button></form><!-- 11DZ_CORE_END --></section><footer class="session-log"><strong id="workflowSessionScore">0 interaction checkpoints</strong><ol id="workflowSessionLaps" aria-label="Round Log"></ol></footer></div><p id="status" class="status" role="status" aria-live="polite"></p></section><aside class="index-mark" aria-hidden="true"><strong>05</strong><span>Course Registration FIELD INDEX</span></aside></div>
  </main>
  <script>
    'use strict';
    const statusOutput = document.querySelector('#status');
    const announce = message => { statusOutput.textContent = message; };
    /* 11DZ_CORE_SCRIPT_START:forms-input-live-validation */
const form = document.querySelector('#demoForm');
    const messages = { name:'Please enter at least two characters', email:'Please enter a valid email address', note:'At least eight characters are required.' };
    function validate(input) { const error = document.querySelector('#' + input.name + 'Error'); const invalid = !input.validity.valid; input.setAttribute('aria-invalid', String(invalid)); if (error) error.textContent = invalid ? messages[input.name] : ''; return !invalid; }
    form.querySelectorAll('input,textarea').forEach(input => input.addEventListener('blur', () => validate(input)));
    form.addEventListener('submit', event => { event.preventDefault(); const inputs = [...form.querySelectorAll('input,textarea')]; const valid = inputs.map(validate).every(Boolean); if (!valid) inputs.find(input => input.getAttribute('aria-invalid') === 'true')?.focus(); announce(valid ? 'The course registration information has passed local validation' : 'Please correct the marked fields'); });
    
    
    
/* 11DZ_CORE_SCRIPT_END */
const workflowBridgeSpec={"name":"forms-input-live-validation","selector":"[data-core-bridge=\"forms-input-live-validation\"]","mode":"click","key":"Enter"};const workflowBridgeCore=document.querySelector('#workflowCore');const workflowBridgeControl=workflowBridgeCore.querySelector(workflowBridgeSpec.selector);if(!workflowBridgeControl)throw new Error('Missing core bridge: '+workflowBridgeSpec.name);const workflowBridgeControlledId=workflowBridgeControl.getAttribute('aria-controls');const workflowBridgeControlled=workflowBridgeControlledId?document.getElementById(workflowBridgeControlledId):null;workflowBridgeCore.dataset.workflowBridge=workflowBridgeSpec.name;workflowBridgeCore.dataset.workflowVersion='0';function workflowBridgeSerialize(){const visualNode=workflowBridgeCore.firstElementChild||workflowBridgeCore;const visual=getComputedStyle(visualNode);const outputs=[...workflowBridgeCore.querySelectorAll('output,[role="status"],[aria-live],meter,progress')].map(node=>node.textContent.trim()+'|'+node.getAttribute('aria-valuenow')+'|'+node.getAttribute('value'));const canvas=[...workflowBridgeCore.querySelectorAll('canvas')].map(node=>{try{return node.toDataURL().slice(-160);}catch{return 'canvas-unavailable';}});return JSON.stringify({html:workflowBridgeCore.innerHTML,status:statusOutput.textContent,outputs,canvas,visual:[visual.display,visual.visibility,visual.opacity,visual.transform,visual.filter,visual.backgroundColor,visual.width,visual.height],scroll:workflowBridgeSpec.mode==='scroll'?workflowBridgeControl.scrollTop:null});}let workflowBridgeLastEffect=workflowBridgeSerialize();function workflowBridgeSummary(){const label=(workflowBridgeControl.getAttribute('aria-label')||workflowBridgeControl.textContent||workflowBridgeControl.value||workflowBridgeSpec.name).trim().replace(/\s+/g,' ').slice(0,72);return label+' · Core Version '+workflowBridgeCore.dataset.workflowVersion;}function workflowBridgeCommit(){const effect=workflowBridgeSerialize();if(effect===workflowBridgeLastEffect)return {changed:false,summary:workflowBridgeSummary()};workflowBridgeLastEffect=effect;workflowBridgeCore.dataset.workflowVersion=String(Number(workflowBridgeCore.dataset.workflowVersion||0)+1);return {changed:true,summary:workflowBridgeSummary()};}function workflowBridgeScheduleCommit(){queueMicrotask(workflowBridgeCommit);setTimeout(workflowBridgeCommit,0);}workflowBridgeControl.addEventListener("click",workflowBridgeScheduleCommit);const workflowBridgeStateTargets=new Set(workflowBridgeCore.querySelectorAll('dialog'));if(workflowBridgeControlled&&workflowBridgeCore.contains(workflowBridgeControlled))workflowBridgeStateTargets.add(workflowBridgeControlled);workflowBridgeStateTargets.forEach(target=>['close','cancel','toggle'].forEach(eventName=>target.addEventListener(eventName,workflowBridgeScheduleCommit)));function workflowBridgeActivate(){workflowBridgeControl.focus();workflowBridgeControl.click();const result=workflowBridgeCommit();setTimeout(workflowBridgeCommit,0);return result;}function workflowBridgeReset(){workflowBridgeCore.dataset.workflowVersion='0';workflowBridgeLastEffect=workflowBridgeSerialize();}
const workflowSessionCore=document.querySelector('#workflowCore');const workflowSessionToggle=document.querySelector('#workflowSessionToggle');const workflowSessionLength=document.querySelector('#workflowSessionLength');const workflowSessionState={phase:'ready',elapsed:0,limit:Number(workflowSessionLength.value),checkpoints:[],timer:null};function workflowSessionFormat(seconds){return String(Math.floor(seconds/60)).padStart(2,'0')+':'+String(seconds%60).padStart(2,'0');}function workflowSessionDrive(){const percent=Math.min(100,Math.round(workflowSessionState.elapsed/workflowSessionState.limit*100));document.querySelector('#workflowSessionClock').textContent=workflowSessionFormat(Math.max(0,workflowSessionState.limit-workflowSessionState.elapsed));const progress=document.querySelector('#workflowSessionProgress');progress.setAttribute('aria-valuenow',String(percent));progress.querySelector('i').style.width=percent+'%';workflowSessionCore.dataset.sessionPhase=workflowSessionState.phase;document.querySelector('#workflowSessionScore').textContent=workflowSessionState.checkpoints.length+' interactive checkpoints';}function workflowSessionLap(label){workflowSessionState.checkpoints.push({label,at:workflowSessionState.elapsed});const item=document.createElement('li');item.textContent=label+' · '+workflowSessionFormat(workflowSessionState.elapsed);document.querySelector('#workflowSessionLaps').append(item);workflowSessionDrive();}function workflowSessionStop(complete=false){clearInterval(workflowSessionState.timer);workflowSessionState.timer=null;workflowSessionState.phase=complete?'complete':'paused';workflowSessionToggle.textContent=complete?'Restart':'Continue round';workflowSessionToggle.setAttribute('aria-pressed','false');workflowSessionDrive();announce(complete?'Course selection plan round complete':'Round paused');}function workflowSessionStart(){if(workflowSessionState.phase==='complete'){workflowSessionState.elapsed=0;workflowSessionState.checkpoints=[];document.querySelector('#workflowSessionLaps').replaceChildren();}workflowSessionState.phase='running';workflowSessionToggle.textContent='Pause round';workflowSessionToggle.setAttribute('aria-pressed','true');const bridge=workflowBridgeActivate();workflowSessionLap(bridge.summary);clearInterval(workflowSessionState.timer);workflowSessionState.timer=setInterval(()=>{workflowSessionState.elapsed+=1;if(workflowSessionState.elapsed>=workflowSessionState.limit){workflowSessionStop(true);return;}workflowSessionDrive();},1000);workflowSessionDrive();announce('Course Enrollment Round has started · '+bridge.summary);}workflowSessionToggle.addEventListener('click',()=>workflowSessionState.phase==='running'?workflowSessionStop():workflowSessionStart());workflowSessionLength.addEventListener('input',()=>{workflowSessionState.limit=Number(workflowSessionLength.value);workflowSessionState.elapsed=Math.min(workflowSessionState.elapsed,workflowSessionState.limit);workflowSessionDrive();});workflowSessionCore.addEventListener('keydown',event=>{if(event.key==='Enter'||event.key===' '){workflowSessionLap('Keyboard Interaction');}});workflowSessionCore.addEventListener('click',event=>{if(event.target.closest('[data-core-bridge]'))workflowSessionLap('Core action · '+workflowBridgeSummary());});document.addEventListener('visibilitychange',()=>{if(document.hidden&&workflowSessionState.phase==='running')workflowSessionStop();});workflowSessionDrive();
workflowBridgeReset();
  </script>
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