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Authnum.class.php 下载
复制代码 代码如下:
<?php
session_start();
class Authnum {
//图片对象、宽度、高度、验证码长度
private $im;
private $im_width;
private $im_height;
private $len;
//随机字符串、y轴坐标值、随机颜色
private $randnum;
private $y;
private $randcolor;
//背景色的红绿蓝，默认是浅灰色
public $red=238;
public $green=238;
public $blue=238;
/**
* 可选设置：验证码类型、干扰点、干扰线、Y轴随机
* 设为 false 表示不启用
**/
//默认是大小写数字混合型，1 2 3 分别表示 小写、大写、数字型
public $ext_num_type='''';
public $ext_pixel = false; //干扰点
public $ext_line = false; //干扰线
public $ext_rand_y= true; //Y轴随机
function __construct ($len=4,$im_width='''',$im_height=25) {
// 验证码长度、图片宽度、高度是实例化类时必需的数据
$this->len = $len; $im_width = $len * 15;
$this->im_width = $im_width;
$this->im_height= $im_height;
$this->im = imagecreate($im_width,$im_height);
}
// 设置图片背景颜色，默认是浅灰色背景
function set_bgcolor () {
imagecolorallocate($this->im,$this->red,$this->green,$this->blue);
}
// 获得任意位数的随机码
function get_randnum () {
$an1 = ''abcdefghijklmnopqrstuvwxyz'';
$an2 = ''ABCDEFGHIJKLMNOPQRSTUVWXYZ'';
$an3 = ''0123456789'';
if ($this->ext_num_type == '''') $str = $an1.$an2.$an3;
if ($this->ext_num_type == 1) $str = $an1;
if ($this->ext_num_type == 2) $str = $an2;
if ($this->ext_num_type == 3) $str = $an3;
for ($i = 0; $i < $this->len; $i++) {
$start = rand(1,strlen($str) - 1);
$randnum .= substr($str,$start,1);
}
$this->randnum = $randnum;
SESSION[an] = $this->randnum;
}
// 获得验证码图片Y轴
function get_y () {
if ($this->ext_rand_y) $this->y = rand(5, $this->im_height/5);
else $this->y = $this->im_height / 4 ;
}
// 获得随机色
function get_randcolor () {
$this->randcolor = imagecolorallocate($this->im,rand(0,100),rand(0,150),rand(0,200));
}
// 添加干扰点
function set_ext_pixel () {
if ($this->ext_pixel) {
for($i = 0; $i < 100; $i++){
$this->get_randcolor();
imagesetpixel($this->im, rand()%100, rand()%100, $this->randcolor);
}
}
}
// 添加干扰线
function set_ext_line () {
if ($this->ext_line) {
for($j = 0; $j < 2; $j++){
$rand_x = rand(2, $this->im_width);
$rand_y = rand(2, $this->im_height);
$rand_x2 = rand(2, $this->im_width);
$rand_y2 = rand(2, $this->im_height);
$this->get_randcolor();
imageline($this->im, $rand_x, $rand_y, $rand_x2, $rand_y2, $this->randcolor);
}
}
}
/**创建验证码图像：
* 建立画布（__construct函数）
* 设置画布背景（$this->set_bgcolor();）
* 获取随机字符串（$this->get_randnum ();）
* 文字写到图片上（imagestring函数）
* 添加干扰点/线（$this->set_ext_line(); $this->set_ext_pixel();）
* 输出图片
**/
function create () {
$this->set_bgcolor();
$this->get_randnum ();
for($i = 0; $i < $this->len; $i++){
$font = rand(4,6);
$x = $i/$this->len * $this->im_width + rand(1, $this->len);
$this->get_y();
$this->get_randcolor();
imagestring($this->im, $font,