如何用脚本生成简单验证码

wen 实用脚本 2026-07-30 84
<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">简单验证码 · 脚本生成</title>
    <!-- 干净简洁，无外部依赖 -->
    <style>
        * {
            box-sizing: border-box;
        }
        body {
            background: #f5f7fa;
            min-height: 100vh;
            margin: 0;
            display: flex;
            justify-content: center;
            align-items: center;
            font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
        }
        .card {
            background: white;
            border-radius: 32px;
            padding: 2rem 2.5rem 2.5rem;
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.06), 0 8px 16px rgba(0, 0, 0, 0.04);
            text-align: center;
            max-width: 460px;
            width: 100%;
            transition: 0.2s;
        }
        h2 {
            font-weight: 500;
            font-size: 1.6rem;
            letter-spacing: -0.01em;
            color: #1e293b;
            margin-top: 0;
            margin-bottom: 0.75rem;
        }
        .sub {
            color: #64748b;
            font-size: 0.95rem;
            margin-bottom: 1.8rem;
            border-bottom: 1px solid #e9edf2;
            padding-bottom: 1rem;
        }
        .capture-box {
            background: #f8fafc;
            border-radius: 24px;
            padding: 1.25rem;
            margin-bottom: 1.5rem;
            border: 1px solid #e9edf2;
        }
        canvas {
            display: block;
            margin: 0 auto;
            border-radius: 18px;
            background: white;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.04);
            width: 100%;
            height: auto;
            max-width: 240px;
            aspect-ratio: 4 / 1.4;  /* 保持宽高 120/42 ≈ 2.857, 近似 */
            cursor: pointer;
            transition: box-shadow 0.2s;
        }
        canvas:active {
            box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
        }
        .info-row {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 1rem;
            flex-wrap: wrap;
            margin: 0.5rem 0 0.2rem;
        }
        .captcha-code {
            font-family: 'Courier New', monospace;
            font-size: 1.5rem;
            font-weight: 500;
            letter-spacing: 0.3em;
            color: #0f172a;
            background: #f1f5f9;
            padding: 0.2rem 1rem;
            border-radius: 60px;
            display: inline-block;
            min-width: 6em;
        }
        .btn-group {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 0.8rem;
            margin-top: 1rem;
        }
        .btn {
            background: white;
            border: 1px solid #d1d9e6;
            padding: 0.6rem 1.4rem;
            border-radius: 60px;
            font-size: 0.9rem;
            font-weight: 500;
            color: #1e293b;
            cursor: pointer;
            transition: 0.15s ease;
            display: inline-flex;
            align-items: center;
            gap: 0.4rem;
            box-shadow: 0 1px 2px rgba(0,0,0,0.02);
        }
        .btn-primary {
            background: #1e293b;
            border-color: #1e293b;
            color: white;
            box-shadow: 0 4px 8px rgba(30, 41, 59, 0.12);
        }
        .btn-primary:hover {
            background: #0f172a;
            border-color: #0f172a;
            box-shadow: 0 6px 12px rgba(30, 41, 59, 0.18);
        }
        .btn-primary:active {
            transform: scale(0.96);
        }
        .btn-outline:hover {
            background: #f1f5f9;
            border-color: #b0c0d4;
        }
        .btn-outline:active {
            background: #e2e8f0;
            transform: scale(0.96);
        }
        .footnote {
            font-size: 0.8rem;
            color: #94a3b8;
            margin-top: 1.6rem;
            border-top: 1px solid #ecf1f7;
            padding-top: 1.2rem;
        }
        .footnote span {
            background: #ecf1f7;
            padding: 0.1rem 0.6rem;
            border-radius: 30px;
            font-family: monospace;
        }
    </style>
</head>
<body>
<div class="card">
    <h2>🛡️ 验证码工坊</h2>
    <div class="sub">点击图片 · 随机刷新</div>
    <div class="capture-box">
        <!-- 验证码画布：宽240x90 比实际稍大，但保留清晰度，内部绘制按比例 -->
        <canvas id="captchaCanvas" width="240" height="90"></canvas>
    </div>
    <div class="info-row">
        <span class="captcha-code" id="codeDisplay">A7K2</span>
    </div>
    <div class="btn-group">
        <button class="btn btn-primary" id="refreshBtn">⟳ 刷新</button>
        <button class="btn btn-outline" id="copyBtn">📋 复制</button>
    </div>
    <div class="footnote">
        轻触 canvas 或点击刷新 · 自动生成4位字母数字
    </div>
</div>
<script>
    (function() {
        // ----- 核心配置 -----
        const canvas = document.getElementById('captchaCanvas');
        const ctx = canvas.getContext('2d');
        const codeDisplay = document.getElementById('codeDisplay');
        // 图形参数 (适应 canvas 240x90)
        const W = 240, H = 90;
        canvas.width = W;
        canvas.height = H;
        // 字符集 (剔除容易混淆的 0/O, 1/I/l 等)
        const CHARSET = 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789';
        const CODE_LENGTH = 4;
        // 当前验证码 (纯大写字母+数字)
        let currentCode = '';
        // ----- 生成随机验证码 -----
        function generateRandomCode() {
            let code = '';
            for (let i = 0; i < CODE_LENGTH; i++) {
                const idx = Math.floor(Math.random() * CHARSET.length);
                code += CHARSET[idx];
            }
            return code;
        }
        // ----- 绘制验证码 (带干扰) -----
        function drawCaptcha(code) {
            // 清空背景 (使用柔和底色)
            ctx.fillStyle = '#f2f5fa';
            ctx.fillRect(0, 0, W, H);
            // 1️⃣ 绘制噪点背景 (浅色圆点)
            ctx.save();
            for (let i = 0; i < 120; i++) {
                const x = Math.random() * W;
                const y = Math.random() * H;
                const radius = Math.random() * 3.5 + 1.2;
                const gray = 160 + Math.floor(Math.random() * 60);
                ctx.beginPath();
                ctx.arc(x, y, radius, 0, Math.PI * 2);
                ctx.fillStyle = `rgba(${gray}, ${gray+20}, ${gray+40}, 0.15)`;
                ctx.fill();
            }
            ctx.restore();
            // 2️⃣ 随机干扰线条 (2~3条)
            ctx.save();
            for (let i = 0; i < 2 + Math.floor(Math.random() * 2); i++) {
                ctx.beginPath();
                const startX = Math.random() * W * 0.2;
                const startY = Math.random() * H;
                const endX = W * 0.6 + Math.random() * W * 0.4;
                const endY = Math.random() * H;
                ctx.moveTo(startX, startY);
                // 曲线路径 制造波浪
                const cpx1 = (startX + endX) / 3 + (Math.random() - 0.5) * 50;
                const cpy1 = Math.random() * H;
                const cpx2 = (startX + endX) * 0.7 + (Math.random() - 0.5) * 40;
                const cpy2 = Math.random() * H;
                ctx.bezierCurveTo(cpx1, cpy1, cpx2, cpy2, endX, endY);
                ctx.strokeStyle = `rgba(60, 80, 120, ${0.2 + Math.random() * 0.25})`;
                ctx.lineWidth = 1.2 + Math.random() * 2.2;
                ctx.stroke();
            }
            ctx.restore();
            // 3️⃣ 绘制文字 (核心验证码)
            ctx.save();
            const charCount = code.length;
            const baseX = 20;             // 起始X偏移
            const spacing = (W - baseX * 1.8) / (charCount - 0.5); // 字符间距
            const fontSize = 36 + Math.floor(Math.random() * 8);   // 36~43
            ctx.font = `bold ${fontSize}px 'Courier New', monospace, 'Segoe UI'`;
            ctx.textBaseline = 'middle';
            ctx.textAlign = 'center';
            for (let i = 0; i < charCount; i++) {
                const ch = code[i];
                // 每个字符独立坐标 + 随机偏移 + 旋转
                const x = baseX + i * spacing + (Math.random() - 0.5) * 12;
                const y = H / 2 + (Math.random() - 0.5) * 16;
                const angle = (Math.random() - 0.5) * 0.35;  // -17° ~ 17°
                ctx.save();
                ctx.translate(x, y);
                ctx.rotate(angle);
                // 随机颜色 (明亮但有区别)
                const hue = 200 + Math.floor(Math.random() * 70); // 蓝绿到橙紫
                const sat = 45 + Math.floor(Math.random() * 40);  // 50~85
                const lig = 30 + Math.floor(Math.random() * 30); // 30~60
                ctx.fillStyle = `hsl(${hue}, ${sat}%, ${lig}%)`;
                // 轻微阴影增强可读性
                ctx.shadowColor = 'rgba(0,0,0,0.08)';
                ctx.shadowBlur = 6;
                ctx.shadowOffsetX = 2;
                ctx.shadowOffsetY = 2;
                // 描边 (细白边增加辨识)
                ctx.strokeStyle = 'rgba(255,255,240,0.25)';
                ctx.lineWidth = 1.2;
                ctx.strokeText(ch, 0, 0);
                ctx.fillText(ch, 0, 0);
                ctx.restore();
            }
            ctx.restore();
            // 4️⃣ 随机额外干扰 (细碎小点 & 短线)
            ctx.save();
            for (let i = 0; i < 20; i++) {
                const x = Math.random() * W;
                const y = Math.random() * H;
                ctx.beginPath();
                ctx.arc(x, y, 1 + Math.random() * 2.5, 0, Math.PI * 2);
                ctx.fillStyle = `rgba(50,60,80,${0.1 + Math.random() * 0.25})`;
                ctx.fill();
            }
            // 少量短线
            for (let i = 0; i < 5; i++) {
                const x1 = Math.random() * W;
                const y1 = Math.random() * H;
                const x2 = x1 + (Math.random() - 0.5) * 40;
                const y2 = y1 + (Math.random() - 0.5) * 18;
                ctx.beginPath();
                ctx.moveTo(x1, y1);
                ctx.lineTo(x2, y2);
                ctx.strokeStyle = `rgba(70,80,100,${0.08 + Math.random() * 0.15})`;
                ctx.lineWidth = 0.8 + Math.random() * 1.5;
                ctx.stroke();
            }
            ctx.restore();
            // 5️⃣ 外边框 / 装饰 (极浅线)
            ctx.save();
            ctx.strokeStyle = 'rgba(200,210,225,0.3)';
            ctx.lineWidth = 1.5;
            ctx.strokeRect(2, 2, W-4, H-4);
            ctx.restore();
        }
        // ----- 刷新验证码 (生成+绘制+更新UI) -----
        function refreshCaptcha() {
            const newCode = generateRandomCode();
            currentCode = newCode;
            drawCaptcha(newCode);
            codeDisplay.textContent = newCode;
        }
        // ----- 复制验证码到剪贴板 (带反馈) -----
        async function copyCodeToClipboard() {
            const code = currentCode || codeDisplay.textContent;
            if (!code) return;
            try {
                await navigator.clipboard.writeText(code);
                // 轻提示 (通过按钮文本闪烁)
                const copyBtn = document.getElementById('copyBtn');
                const originalText = copyBtn.innerText;
                copyBtn.innerText = '✅ 已复制';
                copyBtn.style.transition = '0.1s';
                setTimeout(() => {
                    copyBtn.innerText = originalText;
                }, 1000);
            } catch (err) {
                // fallback (针对部分环境)
                const textarea = document.createElement('textarea');
                textarea.value = code;
                document.body.appendChild(textarea);
                textarea.select();
                document.execCommand('copy');
                document.body.removeChild(textarea);
                alert('验证码已复制: ' + code);
            }
        }
        // ----- 初始化 & 事件绑定 -----
        function init() {
            // 首次生成
            refreshCaptcha();
            // 刷新按钮
            document.getElementById('refreshBtn').addEventListener('click', function(e) {
                e.preventDefault();
                refreshCaptcha();
            });
            // 复制按钮
            document.getElementById('copyBtn').addEventListener('click', function(e) {
                e.preventDefault();
                copyCodeToClipboard();
            });
            // 点击canvas刷新 (体验)
            canvas.addEventListener('click', function(e) {
                // 避免误触菜单等
                refreshCaptcha();
            });
            // 键盘快捷键: R 刷新 (可选项)
            document.addEventListener('keydown', function(e) {
                if (e.key === 'r' || e.key === 'R') {
                    // 如果焦点不在输入框等，执行刷新 (但防止意外的页面刷新)
                    if (!e.target.closest('input, textarea, select, button')) {
                        e.preventDefault();
                        refreshCaptcha();
                    }
                }
            });
            // 额外装饰: 悬停提示
            canvas.title = '点击刷新验证码';
        }
        // 启动所有
        init();
    })();
</script>
</body>
</html>