php生成简单的验证码代码
<?php
session_start();
//验证码高宽
$verify_width = 150;
$verify_height = 50;
$verify_length = 4;
//创建画布
$verify_img = imagecreatetruecolor($verify_width, $verify_height);
//生成随机背景颜色
$bg_color = imagecolorallocate($verify_img, rand(0, 255), rand(0, 255), rand(0, 255));
//填充背景色
imagefill($verify_img, 0, 0, $bg_color);
//绘制点
for ($i = 1; $i <= 20; $i++) {
$color = imagecolorallocate($verify_img, rand(0, 255), rand(0, 255), rand(0, 255));
imagesetpixel($verify_img, rand(0, $verify_width), rand(0, $verify_height), $color);
}
//绘制线
for ($i = 1; $i <= 5; $i++) {
$color = imagecolorallocate($verify_img, rand(0, 255), rand(0, 255), rand(0, 255));
imageline($verify_img, rand(0, $verify_width), rand(0, $verify_height), rand(0, $verify_width), rand(0, $verify_height), $color);
}
//绘制矩形
for ($i = 1; $i <= 3; $i++) {
$color = imagecolorallocate($verify_img, rand(0, 255), rand(0, 255), rand(0, 255));
imagerectangle($verify_img, rand(0, $verify_width), rand(0, $verify_height), rand(0, $verify_width), rand(0, $verify_height), $color);
}
//绘制椭圆
for ($i = 1; $i <= 3; $i++) {
$color = imagecolorallocate($verify_img, rand(0, 255), rand(0, 255), rand(0, 255));
imageellipse($verify_img, rand(0, $verify_width), rand(0, $verify_height), rand(0, $verify_width), rand(0, $verify_height), $color);
}
//生成随机字符串
$arr = range('a', 'z');
$str = implode('', $arr);
$str2 = '1234567890' . $str . strtoupper($str);
$str2 = str_shuffle($str2);
$rand_str = substr($str2, 5, $verify_length);
//存储验证码
$_SESSION['verify']['code'] = md5($rand_str);
$_SESSION['verify']['time'] = time();
//在图片中写入文字
$color = imagecolorallocate($verify_img, rand(0, 255), rand(0, 255), rand(0, 255));
//imagestring($verify_img,100,0,0,$rand_str,$color);
//验证码字体设置
$font_x = 10;
$font_y = 45;
$font_file = "font/msyh.ttc";
imagefttext($verify_img, 40, 0, $font_x, $font_y, $color, $font_file, $rand_str);
//生成图片
header("Content-type:image/png");
imagepng($verify_img);使用方法:
<div> <img src="verifyCode.php" width="40" > </div>
