save html form data to json file using javascript

<div class="container">
        <h1>User Registration Form</h1>
        <p class="subtitle">Fill out the form and save data as JSON</p>

        <form id="userForm">
            <div class="form-group">
                <label for="fullName">Full Name *</label>
                <input type="text" id="fullName" name="fullName" required>
            </div>

            <div class="form-group">
                <label for="email">Email Address *</label>
                <input type="email" id="email" name="email" required>
            </div>

            <div class="form-group">
                <label for="phone">Phone Number</label>
                <input type="tel" id="phone" name="phone">
            </div>

            <div class="form-group">
                <label for="country">Country *</label>
                <select id="country" name="country" required>
                    <option value="">Select Country</option>
                    <option value="USA">United States</option>
                    <option value="UK">United Kingdom</option>
                    <option value="Canada">Canada</option>
                    <option value="Pakistan">Pakistan</option>
                    <option value="India">India</option>
                    <option value="Australia">Australia</option>
                    <option value="Germany">Germany</option>
                    <option value="France">France</option>
                </select>
            </div>

            <div class="form-group">
                <label for="message">Message</label>
                <textarea id="message" name="message"></textarea>
            </div>

            <div class="button-group">
                <button type="submit" class="button">Save to JSON</button>
                <button type="button" class="button button-secondary" id="downloadBtn">Download JSON</button>
            </div>
        </form>

        <div class="success-message" id="successMessage">
            ✓ Form data saved successfully!
        </div>

        <div class="json-display" id="jsonDisplay">
            <div class="json-header">
                <span class="json-label">JSON Output</span>
                <button class="copy-json-btn" id="copyJsonBtn">Copy JSON</button>
            </div>
            <pre id="jsonOutput"></pre>
        </div>

        <div class="saved-entries" id="savedEntries">
            <div class="entries-header">
                <h2 class="entries-title">Saved Entries</h2>
                <button class="button button-secondary" id="clearBtn" style="flex: none; padding: 8px 16px; font-size: 14px;">Clear All</button>
            </div>
            <div id="entriesList">
                <div class="no-entries">No entries saved yet</div>
            </div>
        </div>
    </div>

   * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
            background: linear-gradient(135deg, #1e3c72 0%, #2a5298 50%, #7e8ba3 100%);
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            padding: 20px;
        }

        .container {
            background: white;
            border-radius: 16px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4);
            padding: 40px;
            max-width: 600px;
            width: 100%;
        }

        h1 {
            font-size: 28px;
            color: #1e3c72;
            margin-bottom: 8px;
            font-weight: 600;
        }

        .subtitle {
            color: #666;
            font-size: 14px;
            margin-bottom: 32px;
        }

        .form-group {
            margin-bottom: 24px;
        }

        label {
            display: block;
            font-size: 14px;
            font-weight: 500;
            color: #333;
            margin-bottom: 8px;
        }

        input, select, textarea {
            width: 100%;
            padding: 12px 16px;
            font-size: 15px;
            border: 2px solid #e0e0e0;
            border-radius: 8px;
            transition: all 0.3s ease;
            font-family: inherit;
        }

        input:focus, select:focus, textarea:focus {
            outline: none;
            border-color: #1e3c72;
            box-shadow: 0 0 0 3px rgba(30, 60, 114, 0.1);
        }

        textarea {
            resize: vertical;
            min-height: 100px;
        }

        .button-group {
            display: flex;
            gap: 12px;
            margin-top: 32px;
        }

        .button {
            flex: 1;
            padding: 14px 24px;
            background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
            color: white;
            border: none;
            border-radius: 8px;
            font-size: 16px;
            font-weight: 600;
            cursor: pointer;
            transition: transform 0.2s, box-shadow 0.2s;
        }

        .button:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(30, 60, 114, 0.3);
        }

        .button:active {
            transform: translateY(0);
        }

        .button-secondary {
            background: linear-gradient(135deg, #6c757d 0%, #868e96 100%);
        }

        .json-display {
            margin-top: 32px;
            padding: 24px;
            background: #1e1e1e;
            border-radius: 12px;
            display: none;
        }

        .json-display.active {
            display: block;
        }

        .json-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 16px;
        }

        .json-label {
            color: #00d4ff;
            font-size: 14px;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 0.5px;
        }

        .copy-json-btn {
            padding: 6px 12px;
            background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
            color: white;
            border: none;
            border-radius: 6px;
            font-size: 12px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s;
        }

        .copy-json-btn:hover {
            background: linear-gradient(135deg, #2a5298 0%, #1e3c72 100%);
        }

        .copy-json-btn.copied {
            background: linear-gradient(135deg, #00c853 0%, #00e676 100%);
        }

        pre {
            margin: 0;
            font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
            font-size: 13px;
            line-height: 1.6;
            color: #d4d4d4;
            overflow-x: auto;
        }

        .success-message {
            margin-top: 16px;
            padding: 16px;
            background: linear-gradient(135deg, #00c853 0%, #00e676 100%);
            color: white;
            border-radius: 8px;
            text-align: center;
            font-weight: 500;
            display: none;
        }

        .success-message.active {
            display: block;
            animation: slideIn 0.3s ease;
        }

        @keyframes slideIn {
            from {
                opacity: 0;
                transform: translateY(-10px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .saved-entries {
            margin-top: 32px;
        }

        .entries-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 16px;
        }

        .entries-title {
            font-size: 18px;
            font-weight: 600;
            color: #1e3c72;
        }

        .entry-card {
            padding: 16px;
            background: #f8f9fa;
            border-radius: 8px;
            margin-bottom: 12px;
            border-left: 4px solid #1e3c72;
        }

        .entry-row {
            display: flex;
            margin-bottom: 8px;
        }

        .entry-label {
            font-weight: 600;
            color: #333;
            min-width: 100px;
        }

        .entry-value {
            color: #666;
        }

        .no-entries {
            text-align: center;
            padding: 40px;
            color: #999;
            font-style: italic;
        }

      let savedData = [];

        const form = document.getElementById('userForm');
        const jsonDisplay = document.getElementById('jsonDisplay');
        const jsonOutput = document.getElementById('jsonOutput');
        const successMessage = document.getElementById('successMessage');
        const copyJsonBtn = document.getElementById('copyJsonBtn');
        const downloadBtn = document.getElementById('downloadBtn');
        const clearBtn = document.getElementById('clearBtn');
        const entriesList = document.getElementById('entriesList');

        function formToJSON(formElement) {
            const formData = new FormData(formElement);
            const jsonObject = {};
            
            formData.forEach((value, key) => {
                jsonObject[key] = value;
            });

            jsonObject.timestamp = new Date().toISOString();
            jsonObject.id = Date.now();

            return jsonObject;
        }

        function displayJSON(data) {
            const jsonString = JSON.stringify(data, null, 2);
            jsonOutput.textContent = jsonString;
            jsonDisplay.classList.add('active');
        }

        function showSuccessMessage() {
            successMessage.classList.add('active');
            setTimeout(() => {
                successMessage.classList.remove('active');
            }, 3000);
        }

        function updateEntriesList() {
            if (savedData.length === 0) {
                entriesList.innerHTML = '<div class="no-entries">No entries saved yet</div>';
                return;
            }

            entriesList.innerHTML = savedData.map(entry => `
                <div class="entry-card">
                    <div class="entry-row">
                        <span class="entry-label">Name:</span>
                        <span class="entry-value">${entry.fullName}</span>
                    </div>
                    <div class="entry-row">
                        <span class="entry-label">Email:</span>
                        <span class="entry-value">${entry.email}</span>
                    </div>
                    <div class="entry-row">
                        <span class="entry-label">Country:</span>
                        <span class="entry-value">${entry.country}</span>
                    </div>
                    <div class="entry-row">
                        <span class="entry-label">Saved:</span>
                        <span class="entry-value">${new Date(entry.timestamp).toLocaleString()}</span>
                    </div>
                </div>
            `).join('');
        }

        form.addEventListener('submit', (e) => {
            e.preventDefault();
            
            const jsonData = formToJSON(form);
            savedData.push(jsonData);
            
            displayJSON(jsonData);
            showSuccessMessage();
            updateEntriesList();
            
            form.reset();
        });

        copyJsonBtn.addEventListener('click', async () => {
            try {
                await navigator.clipboard.writeText(jsonOutput.textContent);
                copyJsonBtn.textContent = 'Copied!';
                copyJsonBtn.classList.add('copied');
                
                setTimeout(() => {
                    copyJsonBtn.textContent = 'Copy JSON';
                    copyJsonBtn.classList.remove('copied');
                }, 2000);
            } catch (err) {
                console.error('Failed to copy:', err);
            }
        });

        downloadBtn.addEventListener('click', () => {
            if (savedData.length === 0) {
                alert('No data to download. Please submit the form first.');
                return;
            }

            const dataToDownload = savedData.length === 1 ? savedData[0] : savedData;
            const jsonString = JSON.stringify(dataToDownload, null, 2);
            const blob = new Blob([jsonString], { type: 'application/json' });
            const url = URL.createObjectURL(blob);
            
            const a = document.createElement('a');
            a.href = url;
            a.download = `form-data-${Date.now()}.json`;
            document.body.appendChild(a);
            a.click();
            document.body.removeChild(a);
            URL.revokeObjectURL(url);
        });

        clearBtn.addEventListener('click', () => {
            if (confirm('Are you sure you want to clear all saved entries?')) {
                savedData = [];
                updateEntriesList();
                jsonDisplay.classList.remove('active');
            }
        });