/**
* 输出验证码并把验证码的值保存的session中
* 验证码保存到session的格式为： $_SESSION[self::$seKey] = array('code' => '验证码值', 'time' => '验证码创建时间');
*/
public static function entry($id = '')
{
// 图片宽(px)
self::$imageL || (self::$imageL = self::$length * self::$fontSize * 1.5 + self::$fontSize * 1.5);
// 图片高(px)
self::$imageH || (self::$imageH = self::$fontSize * 2);
// 建立一幅 self::$imageL x self::$imageH 的图像
self::$_image = imagecreate(self::$imageL, self::$imageH);
// 设置背景
imagecolorallocate(self::$_image, self::$bg[0], self::$bg[1], self::$bg[2]);
// 验证码字体随机颜色
self::$_color = imagecolorallocate(self::$_image, mt_rand(1, 120), mt_rand(1, 120), mt_rand(1, 120));
// 验证码使用随机字体
$ttfPath = dirname(__FILE__) . '/captcha/' . (self::$useZh ? 'zhttfs' : 'ttfs') . '/';
$dir = dir($ttfPath);
$ttfs = array();
while (false !== ($file = $dir->read())) {
if ($file[0] != '.' && substr($file, -4) == '.ttf') {
$ttfs[] = $ttfPath . $file;
}
}
$dir->close();
// print_r($ttfs);
// exit;
$ttf = $ttfs[array_rand($ttfs)];
if (self::$useImgBg) {
self::_background();
}
if (self::$useNoise) {
// 绘杂点
self::_writeNoise();
}
if (self::$useCurve) {
// 绘干扰线
self::_writeCurve();
}
// 绘验证码
$code = array();
// 验证码
$codeNX = 0;
// 验证码第N个字符的左边距
for ($i = 0; $i < self::$length; $i++) {
if (self::$useZh) {
$code[$i] = chr(mt_rand(0xb0, 0xf7)) . chr(mt_rand(0xa1, 0xfe));
} else {
$code[$i] = self::$_codeSet[mt_rand(0, 8)];
$codeNX += mt_rand(self::$fontSize * 1.2, self::$fontSize * 1.6);
// 写一个验证码字符
self::$useZh || imagettftext(self::$_image, self::$fontSize, mt_rand(-40, 40), $codeNX, self::$fontSize * 1.5, self::$_color, $ttf, $code[$i]);
}
}
// 保存验证码
isset($_SESSION) || session_start();
if ($id) {
$_SESSION[self::$seKey][$id]['code'] = join('', $code);
// 把校验码保存到session
$_SESSION[self::$seKey][$id]['time'] = time();
// 验证码创建时间
} else {
$_SESSION[self::$seKey]['code'] = join('', $code);
// 把校验码保存到session
$_SESSION[self::$seKey]['time'] = time();
// 验证码创建时间
}
self::$useZh && imagettftext(self::$_image, self::$fontSize, 0, (self::$imageL - self::$fontSize * self::$length * 1.2) / 3, self::$fontSize * 1.5, self::$_color, $ttf, iconv("GB2312", "UTF-8", join('', $code)));
header('Cache-Control: private, max-age=0, no-store, no-cache, must-revalidate');
header('Cache-Control: post-check=0, pre-check=0', false);
header('Pragma: no-cache');
header("content-type: image/png");
// 输出图像
imagepng(self::$_image);
imagedestroy(self::$_image);
}
