public function code()
{
//主要参数
if($font_size == 0) $font_size = 20;
if($img_width == 0) $img_width = 110;
if($img_height == 0) $img_height = 50;
if($word_type == 0) $word_type = 3; // 1:数字 2:英文 3:混合
$font_file = 'E:\phpStudy\PHPTutorial\WWW\thinkphp_3.2.3_full\Application\Home\Controller\SIDESHOW.TTF';//字体的路径
//创建图片,并设置背景色
$im = @imagecreate($img_width, $img_height);
imagecolorallocate($im, 192,192,192);
//获取随机字符
if($word_type == 1) {
$verifyCode = implode('', range(2, 9));
}elseif ($word_type == 2) {
$verifyCode = implode('', range('A', 'Z'));
}else{
$verifyCode = implode('', array_merge(range(2, 9),range('A', 'Z')));
$verifyCode = str_replace(array('I','O'), array('P','N'), $verifyCode);
}
//打乱字符串
$verifyCode = str_shuffle($verifyCode);
$rndstring = substr($verifyCode,0,4);
//echo $rndstring;exit;
$rndcodelen = strlen($rndstring);
//干扰线
for($i = 0; $i < 5; $i++) {
$color = imagecolorallocate($im, 0, 0, 0);
imageline($im, rand(0, $img_width), rand(0, $img_height), rand(0, $img_width), rand(0, $img_height), $color);
}
//画边框
//$bordercolor = imagecolorallocate($im, 0, 0, 0);
//imagerectangle($im, 0, 0, $img_width-1, $img_height-1, $bordercolor);
//输出文字
for($i = 0;$i < $rndcodelen;$i++){
$rndstring[$i] = strtoupper($rndstring[$i]);
$c_fontColor = imagecolorallocate($im, 0, 0, 0);
$y_pos = $i == 0 ? 10 : $i * ($font_size + 8);
$c = mt_rand(0, 15);
imagettftext($im, $font_size, $c, $y_pos, 35, $c_fontColor, $font_file, $rndstring[$i]);
}
header("Pragma:no-cache\r\n");
header("Cache-Control:no-cache\r\n");
header("Expires:0\r\n");
if(function_exists("imagejpeg")){
header("content-type:image/jpeg\r\n");
imagejpeg($im);
}else{
header("content-type:image/png\r\n");
imagepng($im);
}
imagedestroy($im);
exit();
}