php图片验证码类,php图片验证码类

[php]

/**

* 图片验证码类

* 生成图片类型验证码，验证码包含数字和大写字母，session中存放md5加密后的验证码

*

* 使用方法：

* $captcha = new Catpcha();

* $captcha->buildAndExportImage();

*

* 作          者: luojing

* 创建时间: 2013-3-27 上午11:42:12

*/

class Captcha {

private $width;//宽度

private $height; //高度

private $codeNum;//验证码字符数量

private $image;//验证码图像资源

private $sessionKey;//session中保存的名字

private $captcha;//验证码字符串

const charWidth = 10;//单个字符宽度,根据输出字符大小而变

/**

* 创建验证码类，初始化相关参数

* @param  $width 图片宽度

* @param  $height 图片高度

* @param  $codeNum 验证码字符数量

* @param  $sessionKey session中保存的名字

*/

function __construct($width = 50, $height = 20, $codeNum = 4, $sessionKey = 'captcha') {

$this->width = $width;

$this->height = $height;

$this->codeNum = $codeNum;

$this->sessionKey = $sessionKey;

//保证最小高度和宽度

if($height < 20) {

$this->height = 20;

}

if($width < ($codeNum * self::charWidth + 10)) {//左右各保留5像素空隙

$this->width = $codeNum * self::charWidth + 10;

}

}

/**

* 构造并输出验证码图片

*/

public  function buildAndExportImage() {

$this->createImage();

$this->setDisturb();

$this->setCaptcha();

$this->exportImage();

}

/**

* 构造图像，设置底色

*/

private function createImage() {

//创建图像

$this->image = imagecreatetruecolor($this->width, $this->height);

//创建背景色

$bg = imagecolorallocate($this->image, mt_rand(220, 255), mt_rand(220, 255), mt_rand(220, 255));

//填充背景色

imagefilledrectangle($this->image, 0, 0, $this->width - 1, $this->height - 1, $bg);

}

/**

* 设置干扰元素

*/

private function setDisturb() {

//设置干扰点

for($i = 0; $i < 150; $i++) {

$color = imagecolorallocate($this->image, mt_rand(150, 200),  mt_rand(150, 200),  mt_rand(150, 200));

imagesetpixel($this->image, mt_rand(5, $this->width - 10), mt_rand(5, $this->height - 3), $color);

}

//设置干扰线

for($i = 0; $i < 10; $i++) {

$color = imagecolorallocate($this->image, mt_rand(150, 220), mt_rand(150, 220), mt_rand(150, 220));

imagearc($this->image, mt_rand(-10, $this->width), mt_rand(-10, $this->height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $color);

}

//创建边框色

$border = imagecolorallocate($this->image, mt_rand(0, 50), mt_rand(0, 50), mt_rand(0, 50));

//画边框

imagerectangle($this->image, 0, 0, $this->width - 1, $this->height - 1, $border);

}

/**

* 产生并绘制验证码

*/

private function setCaptcha() {

$str = '23456789ABCDEFGHJKLMNPQRSTUVWXYZ';

//生成验证码字符

for($i = 0; $i < $this->codeNum; $i++) {

$this->captcha .= $str{mt_rand(0, strlen($str) - 1)};

}

//绘制验证码

for($i = 0; $i < strlen($this->captcha); $i++) {

$color = imagecolorallocate($this->image, mt_rand(0, 200), mt_rand(0, 200), mt_rand(0, 200));

$x = floor(($this->width - 10)/$this->codeNum);

$x = $x*$i + floor(($x-self::charWidth)/2) + 5;

$y = mt_rand(2, $this->height - 20);

imagechar($this->image, 5, $x, $y, $this->captcha{$i}, $color);

}

}

/*

* 输出图像,验证码保存到session中

*/

private function exportImage() {

if(imagetypes() & IMG_GIF){

header('Content-type:image/gif');

imagegif($this->image);

} else if(imagetypes() & IMG_PNG){

header('Content-type:image/png');

imagepng($this->iamge);

} else if(imagetypes() & IMG_JPEG) {

header('Content-type:image/jpeg');

imagepng($this->iamge);

} else {

imagedestroy($this->image);

die("Don't support image type!");

}

//将验证码信息保存到session中，md5加密

if(!isset($_SESSION)){

session_start();

}

$_SESSION[$this->sessionKey] = md5($this->captcha);

imagedestroy($this->image);

}

function __destruct() {

unset($this->width, $this->height, $this->codeNum,$this->captcha);

}

}

/**

* 图片验证码类

* 生成图片类型验证码，验证码包含数字和大写字母，session中存放md5加密后的验证码

*

* 使用方法：

* $captcha = new Catpcha();

* $captcha->buildAndExportImage();

*

* 作          者: luojing

* 创建时间: 2013-3-27 上午11:42:12

*/

class Captcha {

private $width;//宽度

private $height; //高度

private $codeNum;//验证码字符数量

private $image;//验证码图像资源

private $sessionKey;//session中保存的名字

private $captcha;//验证码字符串

const charWidth = 10;//单个字符宽度,根据输出字符大小而变

/**

* 创建验证码类，初始化相关参数

* @param  $width 图片宽度

* @param  $height 图片高度

* @param  $codeNum 验证码字符数量

* @param  $sessionKey session中保存的名字

*/

function __construct($width = 50, $height = 20, $codeNum = 4, $sessionKey = 'captcha') {

$this->width = $width;

$this->height = $height;

$this->codeNum = $codeNum;

$this->sessionKey = $sessionKey;

//保证最小高度和宽度

if($height < 20) {

$this->height = 20;

}

if($width < ($codeNum * self::charWidth + 10)) {//左右各保留5像素空隙

$this->width = $codeNum * self::charWidth + 10;

}

}

/**

* 构造并输出验证码图片

*/

public  function buildAndExportImage() {

$this->createImage();

$this->setDisturb();

$this->setCaptcha();

$this->exportImage();

}

/**

* 构造图像，设置底色

*/

private function createImage() {

//创建图像

$this->image = imagecreatetruecolor($this->width, $this->height);

//创建背景色

$bg = imagecolorallocate($this->image, mt_rand(220, 255), mt_rand(220, 255), mt_rand(220, 255));

//填充背景色

imagefilledrectangle($this->image, 0, 0, $this->width - 1, $this->height - 1, $bg);

}

/**

* 设置干扰元素

*/

private function setDisturb() {

//设置干扰点

for($i = 0; $i < 150; $i++) {

$color = imagecolorallocate($this->image, mt_rand(150, 200),  mt_rand(150, 200),  mt_rand(150, 200));

imagesetpixel($this->image, mt_rand(5, $this->width - 10), mt_rand(5, $this->height - 3), $color);

}

//设置干扰线

for($i = 0; $i < 10; $i++) {

$color = imagecolorallocate($this->image, mt_rand(150, 220), mt_rand(150, 220), mt_rand(150, 220));

imagearc($this->image, mt_rand(-10, $this->width), mt_rand(-10, $this->height), mt_rand(30, 300), mt_rand(20, 200), 55, 44, $color);

}

//创建边框色

$border = imagecolorallocate($this->image, mt_rand(0, 50), mt_rand(0, 50), mt_rand(0, 50));

//画边框

imagerectangle($this->image, 0, 0, $this->width - 1, $this->height - 1, $border);

}

/**

* 产生并绘制验证码

*/

private function setCaptcha() {

$str = '23456789ABCDEFGHJKLMNPQRSTUVWXYZ';

//生成验证码字符

for($i = 0; $i < $this->codeNum; $i++) {

$this->captcha .= $str{mt_rand(0, strlen($str) - 1)};

}

//绘制验证码

for($i = 0; $i < strlen($this->captcha); $i++) {

$color = imagecolorallocate($this->image, mt_rand(0, 200), mt_rand(0, 200), mt_rand(0, 200));

$x = floor(($this->width - 10)/$this->codeNum);

$x = $x*$i + floor(($x-self::charWidth)/2) + 5;

$y = mt_rand(2, $this->height - 20);

imagechar($this->image, 5, $x, $y, $this->captcha{$i}, $color);

}

}

/*

* 输出图像,验证码保存到session中

*/

private function exportImage() {

if(imagetypes() & IMG_GIF){

header('Content-type:image/gif');

imagegif($this->image);

} else if(imagetypes() & IMG_PNG){

header('Content-type:image/png');

imagepng($this->iamge);

} else if(imagetypes() & IMG_JPEG) {

header('Content-type:image/jpeg');

imagepng($this->iamge);

} else {

imagedestroy($this->image);

die("Don't support image type!");

}

//将验证码信息保存到session中，md5加密

if(!isset($_SESSION)){

session_start();

}

$_SESSION[$this->sessionKey] = md5($this->captcha);

imagedestroy($this->image);

}

function __destruct() {

unset($this->width, $this->height, $this->codeNum,$this->captcha);

}

}