示例

服務類 app\common\lib\captcha

<?php
namespace app\common\lib\captcha;use think\facade\Cache;
use think\facade\Config;
use Exception;class Captcha
{private $im = null; // 驗證碼圖片實例private $color = null; // 驗證碼字體顏色// 默認配置protected $config = ['length'      => 4,      // 驗證碼位數'fontSize'    => 25,     // 字體大小(px)'imageH'      => 0,      // 驗證碼高度'imageW'      => 0,      // 驗證碼寬度'useCurve'    => true,   // 是否畫混淆曲線'useNoise'    => false,  // 是否添加雜點(已禁用)'bg'          => [243, 251, 254], // 背景顏色'fontttf'     => '',     // 字體文件路徑'useZh'       => false,  // 使用中文驗證碼'math'        => false,  // 算術驗證碼'alpha'       => 0,      // 透明度(0-127)'api'         => false,  // API模式'fontPath'    => '',     // 字體文件目錄'bgPath'      => '',     // 背景圖片目錄'expire'      => 1800,   // 驗證碼過期時間(s)];// 簡化后的驗證碼字符集合(僅數字和大寫字母)protected $codeSet = '23456789ABCDEFGHJKLMNPQRSTUVWXYZ';/*** 構造函數* @param array $config 配置參數*/public function __construct(array $config = []){// 合并配置參數$this->config = array_merge($this->config, Config::get('captcha', []), $config);// 設置字體路徑if (empty($this->config['fontPath'])) {$this->config['fontPath'] = __DIR__ . '/ttfs/';}}/*** 生成驗證碼* @param string $uniqueId 前端傳遞的唯一標識(如時間戳)* @return string 圖片二進制內容*/public function create(string $uniqueId = ''): string{// 清理過期緩存$this->clearExpiredCaptchas();// 如果未提供 uniqueId，則生成一個默認值if (empty($uniqueId)) {$uniqueId = uniqid('captcha_');}// 生成驗證碼文本$generator = $this->generate($uniqueId);// 計算圖片寬高$this->config['imageW'] = $this->config['imageW'] ?: $this->config['length'] * $this->config['fontSize'] * 1.5;$this->config['imageH'] = $this->config['imageH'] ?: $this->config['fontSize'] * 2;// 創建圖片資源$this->im = imagecreate((int)$this->config['imageW'], (int)$this->config['imageH']);// 設置背景色$bgColor = imagecolorallocate($this->im,$this->config['bg'][0],$this->config['bg'][1],$this->config['bg'][2]);imagefill($this->im, 0, 0, $bgColor);// 設置字體顏色$this->color = imagecolorallocate($this->im, mt_rand(0, 100), mt_rand(0, 100), mt_rand(0, 100));// 添加干擾線if ($this->config['useCurve']) {$this->writeCurve();}// 繪制驗證碼$text = str_split($generator['value']);$space = $this->config['imageW'] / $this->config['length'];foreach ($text as $index => $char) {// 計算位置$x = $space * $index + mt_rand(5, 10);$y = $this->config['imageH'] / 2 + $this->config['fontSize'] / 2;$angle = mt_rand(-15, 15);imagettftext($this->im,(int)$this->config['fontSize'],$angle,(int)$x,(int)$y,$this->color,$this->getFont(),$char);}ob_start();imagepng($this->im);$content = ob_get_clean();imagedestroy($this->im);return $content;}/*** 驗證驗證碼* @param string $code 用戶輸入的驗證碼* @param string $uniqueId 前端傳遞的唯一標識(如時間戳)* @return bool*/public function check(string $code, string $uniqueId = ''): bool{if (empty($uniqueId)) {return false;}// 從 Cache 中獲取數據$cacheData = Cache::get($uniqueId);if (!$cacheData || time() - $cacheData['time'] > $this->config['expire']) {$this->removeCaptchaFromRecords($uniqueId);return false;}// 驗證碼校驗$result = password_verify(strtoupper($code), $cacheData['key']);return $result;}/*** 生成驗證碼文本* @param string $uniqueId 前端傳遞的唯一標識(如時間戳)* @return array ['value' => 顯示的文本, 'key' => 加密后的驗證碼]*/protected function generate(string $uniqueId): array{$bag = '';$characters = str_split($this->codeSet);for ($i = 0; $i < $this->config['length']; $i++) {$bag .= $characters[random_int(0, count($characters) - 1)];}$key = strtoupper($bag);// 使用 Bcrypt 加密驗證碼$hash = password_hash($key, PASSWORD_BCRYPT, ['cost' => 10]);// 將驗證碼信息存儲到 Cache 中Cache::set($uniqueId, ['key' => $hash,'time' => time(),// 'raw' => $key // 調試用，正式環境移除], $this->config['expire']);// 記錄到清理隊列$this->addCaptchaToRecords($uniqueId);return ['value' => $bag, 'key' => $hash];}/*** 添加驗證碼記錄到清理隊列*/protected function addCaptchaToRecords(string $uniqueId): void{$records = Cache::get('captcha_records', []);$records[$uniqueId] = time() + $this->config['expire'];// 限制最大記錄數，防止內存占用過大if (count($records) > 1000) {$records = array_slice($records, -500, null, true);}Cache::set('captcha_records', $records);}/*** 從清理隊列中移除驗證碼記錄*/protected function removeCaptchaFromRecords(string $uniqueId): void{$records = Cache::get('captcha_records', []);unset($records[$uniqueId]);Cache::set('captcha_records', $records);}/*** 清理過期的驗證碼緩存*/protected function clearExpiredCaptchas(): void{// 每小時清理一次$lastClear = Cache::get('last_captcha_clear', 0);if (time() - $lastClear < 3600) {return;}$records = Cache::get('captcha_records', []);$now = time();$cleaned = false;foreach ($records as $uid => $expireTime) {if ($expireTime < $now) {Cache::delete($uid);unset($records[$uid]);$cleaned = true;}}if ($cleaned) {Cache::set('captcha_records', $records);Cache::set('last_captcha_clear', time());}}/*** 獲取字體文件路徑* @return string* @throws Exception*/protected function getFont(): string{if (!empty($this->config['fontttf'])) {return $this->config['fontttf'];}$fonts = glob($this->config['fontPath'] . '*.ttf') +glob($this->config['fontPath'] . '*.otf');if (empty($fonts)) {throw new Exception('驗證碼字體文件不存在，請檢查字體路徑: ' . $this->config['fontPath']);}return $fonts[array_rand($fonts)];}/*** 畫干擾曲線*/protected function writeCurve(): void{$px = $py = 0;// 曲線前部分$A = mt_rand(1, (int)($this->config['imageH'] / 2)); // 振幅$b = mt_rand((int)(-$this->config['imageH'] / 4), (int)($this->config['imageH'] / 4)); // Y軸偏移$f = mt_rand((int)(-$this->config['imageH'] / 4), (int)($this->config['imageH'] / 4)); // X軸偏移$T = mt_rand($this->config['imageH'], $this->config['imageW'] * 2); // 周期$w = (2 * M_PI) / $T;$px1 = 0; // 起始X坐標$px2 = mt_rand((int)($this->config['imageW'] / 2), (int)($this->config['imageW'] * 0.8)); // 結束X坐標for ($px = $px1; $px <= $px2; $px++) {if ($w != 0) {$py = $A * sin($w * $px + $f) + $b + $this->config['imageH'] / 2;$i = (int)($this->config['fontSize'] / 5);while ($i > 0) {imagesetpixel($this->im, $px + $i, $py + $i, $this->color);$i--;}}}// 曲線后部分$A = mt_rand(1, (int)($this->config['imageH'] / 2));$f = mt_rand((int)(-$this->config['imageH'] / 4), (int)($this->config['imageH'] / 4));$T = mt_rand($this->config['imageH'], $this->config['imageW'] * 2);$w = (2 * M_PI) / $T;$b = $py - $A * sin($w * $px + $f) - $this->config['imageH'] / 2;$px1 = $px2;$px2 = $this->config['imageW'];for ($px = $px1; $px <= $px2; $px++) {if ($w != 0) {$py = $A * sin($w * $px + $f) + $b + $this->config['imageH'] / 2;$i = (int)($this->config['fontSize'] / 5);while ($i > 0) {imagesetpixel($this->im, $px + $i, $py + $i, $this->color);$i--;}}}}
}

控制器調用

// 生成圖形驗證碼public function getCaptcha(){$uid = 'captcha_' . uniqid('', true);$captcha = new \app\common\lib\captcha\Captcha();$img = $captcha->create($uid);return json(['image' => 'data:image/png;base64,'.base64_encode($img),'uid' => $uid]);}// 校驗圖形驗證碼public function checkCaptcha(){$code = input('post.code');$uid = input('post.uid');$captcha = new \app\common\lib\captcha\Captcha();$result = $captcha->check($code, $uid);return json(['success' => $result,'input_code' => $code,'uid' => $uid]);}