1. [代码]制作随机字符串 <?php
print_r(join("",array_merge(range("a","z"),range("a","z"))));
echo '<br />';
$chars = join("",array_merge(range("a","z"),range("a","z"),range("0","9")));
$chars = str_shuffle($chars);
echo $chars;
foreach (range(0, 12) as $number) {
echo $number,'<br />';
}
?>
2. [代码]利用gd库制作验证码 <?php
require_once("string_func.php");
//通过gd库做验证码
//创建画布
/*
* @param $sess_name session名称
* @param $type 验证码样式. 1：纯数字验证码； 2：纯字母验证码； 3：数字和字母混合验证码；
* @param $length 验证码字符数量。
* @param $pixel 干扰点数量
* @param $line 干扰线数量
* */
function image_func($sess_name = "verify",$type = 1,$length = 4,$pixel = 50,$line=3)
{
session_start();
$width = 80;
$height = 30;
$image = imagecreatetruecolor($width, $height);
$white = imagecolorallocate($image, 255, 255, 255);
$black = imagecolorallocate($image, 0, 0, 0);
//填充画布
imagefilledrectangle($image, 1, 1, $width - 2, $height - 2, $white);
$chars = buildrandomstring($type, $length);
$_session[$sess_name] = $chars;
$fontfiles = array("msyh.ttc", "msyhbd.ttc", "simhei.ttf", "simsun.ttc", "deng.ttf", "dengb.ttf", "dengl.ttf");
for ($i = 0; $i < $length; $i++) {
$size = mt_rand(14, 18);
$angle = mt_rand(-15, 15);
$x = 5 + $i * $size;
$y = mt_rand(20, 26);
$fontfile = "fonts/" . $fontfiles[mt_rand(0, count($fontfiles) - 1)];
$color = imagecolorallocate($image, mt_rand(50, 90), mt_rand(80, 120), mt_rand(90, 180));
$text = substr($chars, $i, 1);
imagettftext($image, $size, $angle, $x, $y, $color, $fontfile, $text);
}
if ($pixel) {
for ($i = 0; $i < $pixel; $i++) {
$pointer_color = imagecolorallocate($image, mt_rand(50, 200), mt_rand(50, 200), mt_rand(50, 200));
imagesetpixel($image, mt_rand(0, 80), mt_rand(0, 30), $pointer_color);
}
}
if ($line) {
for ($i = 0; $i < $line; $i++) {
$line_color = imagecolorallocate($image, mt_rand(100, 220), mt_rand(100, 220), mt_rand(100, 220));
imageline($image, mt_rand(0, 80), mt_rand(0, 30), mt_rand(0, 80), mt_rand(0, 30), $line_color);
}
}
header("content-type:image/gif");
imagegif($image);
imagedestroy($image);
}
return image_func('a',1,4,100,3);
?>
3. [代码]效果测试 <!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>title</title>
</head>
<body>
<img src="image_func.php" alt="">
</body>
</html>