本文给大家汇总介绍了3种php编写的图片验证码类，代码都非常的简单实用，有相同需求的小伙伴可以收藏下。

适用于自定义的验证码类！

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Class Image{

private $img;

public $width = 85;

public $height = 25;

public $code;

public $code_len = 4;

public $code_str = "329832983DSDSKDSLKQWEWQ2lkfDSFSDjfdsfdsjwlkfj93290KFDSKJFDSOIDSLK";

public $bg_color = '#DCDCDC';

public $font_size = 16;

public $font = 'font.ttf';

public $font_color = '#000000';

//创建验证码饿字符创

public function create_code(){

$code = '';

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

$code .= $this->code_str[mt_rand(0, strlen($this->code_str)-1)];

}

return $this->code = $code;

}

//输出图像

public function getImage(){

$w = $this->width;

$h = $this->height;

$bg_color = $this->bg_color;

$img = imagecreatetruecolor($w, $h);

$bg_color = imagecolorallocate($img,

hexdec(substr($bg_color, 1,2)), hexdec(substr($bg_color, 3,2)), hexdec(substr($bg_color, 5,2)));

imagefill($img, 0, 0, $bg_color);

$this->img = $img;

$this->create_font();

$this->create_pix();

$this->show_code();

}

//写入验证码

public function create_font(){

$this->create_code();

$color = $this->font_color;

$font_color = imagecolorallocate($this->img, hexdec(substr($color,1,2)), hexdec(substr($color, 3,2)), hexdec(substr($color,5,2)));

$x = $this->width/$this->code_len;

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

$txt_color = imagecolorallocate($this->img, mt_rand(0,100), mt_rand(0, 150), mt_rand(0, 200));

imagettftext($this->img, $this->font_size, mt_rand(-30, 30), $x*$i+mt_rand(3, 6), mt_rand($this->height/1.2, $this->height), $txt_color, $this->font , $this->code[$i]);

//imagestring($this->img, $this->font_size, $x*$i+mt_rand(3, 6),mt_rand(0, $this->height/4) , $this->code[$i], $font_color);

}

$this->font_color = $font_color;

}

//画干扰线

public function create_pix(){

$pix_color= $this->font_color;

for($i=0;$i<100;$i++){

imagesetpixel($this->img, mt_rand(0, $this->width),mt_rand(0, $this->height), $pix_color);

}

for($j=0;$j<4;$j++){

imagesetthickness($this->img, mt_rand(1, 2));

imageline($this->img, mt_rand(0, $this->width), mt_rand(0, $this->height), mt_rand(0, $this->width), mt_rand(0, $this->height), $pix_color);

}

}

//得到验证码

public function getCode(){

return strtoupper($this->code);

}

//输出验证码

private function show_code(){

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

imagepng($this->img);

imagedestroy($this->img);

}

}

我们再来看一例代码：

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

/**

* 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);

}

}

例三：

class ValidationCode {

private $width;

private $height;

private $codeNum;

private $image; //图像资源

private $disturbColorNum;

private $checkCode;

function __construct($width=80, $height=20, $codeNum=4){

$this->width=$width;

$this->height=$height;

$this->codeNum=$codeNum;

$this->checkCode=$this->createCheckCode();

$number=floor($width*$height/15);

if($number > 240-$codeNum){

$this->disturbColorNum= 240-$codeNum;

}else{

$this->disturbColorNum=$number;

}

}

//通过访问该方法向浏览器中输出图像

function showImage($fontFace=""){

//第一步：创建图像背景

$this->createImage();

//第二步：设置干扰元素

$this->setDisturbColor();

//第三步：向图像中随机画出文本

$this->outputText($fontFace);

//第四步：输出图像

$this->outputImage();

}

//通过调用该方法获取随机创建的验证码字符串

function getCheckCode(){

return $this->checkCode;

}

private function createImage(){

//创建图像资源

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

//随机背景色

$backColor=imagecolorallocate($this->image, rand(225, 255), rand(225,255), rand(225, 255));

//为背景添充颜色

imagefill($this->image, 0, 0, $backColor);

//设置边框颜色

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

//画出矩形边框

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

}

private function setDisturbColor(){

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

$color=imagecolorallocate($this->image, rand(0, 255), rand(0, 255), rand(0, 255));

imagesetpixel($this->image, rand(1, $this->width-2), rand(1, $this->height-2), $color);

}

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

$color=imagecolorallocate($this->image, rand(200, 255), rand(200, 255), rand(200, 255));

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

}

}

private function createCheckCode(){

//这里主要产生随机码，从2开始是为了区分1和l

$code="23456789abcdefghijkmnpqrstuvwxyzABCDEFGHIJKMNPQRSTUVWXYZ";

$string='';

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

$char=$code{rand(0, strlen($code)-1)};

$string.=$char;

}

return $string;

}

private function outputText($fontFace=""){

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

$fontcolor=imagecolorallocate($this->image, rand(0, 128), rand(0, 128), rand(0, 128));

if($fontFace==""){

$fontsize=rand(3, 5);

$x=floor($this->width/$this->codeNum)*$i+3;

$y=rand(0, $this->height-15);

imagechar($this->image,$fontsize, $x, $y, $this->checkCode{$i},$fontcolor);

}else{

$fontsize=rand(12, 16);

$x=floor(($this->width-8)/$this->codeNum)*$i+8;

$y=rand($fontSize+5, $this->height);

imagettftext($this->image,$fontsize,rand(-30, 30),$x,$y ,$fontcolor, $fontFace, $this->checkCode{$i});

}

}

}

private function outputImage() {

if(imagetypes() & IMG_GIF){

header("Content-Type:image/gif");

imagepng($this->image);

}else if(imagetypes() & IMG_JPG){

header("Content-Type:image/jpeg");

imagepng($this->image);

}else if(imagetypes() & IMG_PNG){

header("Content-Type:image/png");

imagepng($this->image);

}else if(imagetypes() & IMG_WBMP){

header("Content-Type:image/vnd.wap.wbmp");

imagepng($this->image);

}else{

die("PHP不支持图像创建");

}

}

function __destruct(){

imagedestroy($this->image);

}

}

使用如下：

测试，调用验证码类

code.php

session_start();

include "validationcode.class.php";

$code=new ValidationCode(80, 20, 4);

$code->showImage(); //输出到页面中供 注册或登录使用

$_SESSION["code"]=$code->getCheckCode(); //将验证码保存到服务器中