本文給大家匯總介紹了3種php編寫的圖片驗證碼類，代碼都非常的簡單實用，有相同需求的小伙伴可以收藏下。

適用于自定義的驗證碼類！

<?php

/* 

 * To change this license header, choose License Headers in Project Properties.

 * To change this template file, choose Tools | Templates

 * and open the template in the editor.

 */

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';

  //創(chuàng)建驗證碼餓字符創(chuàng)

  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;

  }

  //輸出圖像

  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();

  }

  //寫入驗證碼

  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;

  }

  //畫干擾線

  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);

    }

  }

  //得到驗證碼

  public function getCode(){

    return strtoupper($this->code);

  }

  //輸出驗證碼

  private function show_code(){

    header("Content-type:image/png");

    imagepng($this->img);

    imagedestroy($this->img);

  }

}

我們再來看一例代碼：

生成圖片類型驗證碼，驗證碼包含數(shù)字和大寫字母，session中存放md5加密后的驗證碼

<?php

/**

 * 圖片驗證碼類

 * 生成圖片類型驗證碼，驗證碼包含數(shù)字和大寫字母，session中存放md5加密后的驗證碼

 * 

 * 使用方法：

 * $captcha = new Catpcha();

 * $captcha->buildAndExportImage();

 * 

 * 作     者: luojing

 * 創(chuàng)建時間: 2013-3-27 上午11:42:12

 */

class Captcha {

    private $width;//寬度

    private $height; //高度

    private $codeNum;//驗證碼字符數(shù)量

    private $image;//驗證碼圖像資源

    private $sessionKey;//session中保存的名字

    private $captcha;//驗證碼字符串

    const charWidth = 10;//單個字符寬度,根據(jù)輸出字符大小而變

    /**

     * 創(chuàng)建驗證碼類，初始化相關參數(shù)

     * @param $width 圖片寬度

     * @param $height 圖片高度

     * @param $codeNum 驗證碼字符數(shù)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;

        //保證最小高度和寬度

        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;

        }

    }

    /**

     * 構造并輸出驗證碼圖片

     */

    public function buildAndExportImage() {

        $this->createImage();

        $this->setDisturb();

        $this->setCaptcha();

        $this->exportImage();

    }

    /**

     * 構造圖像，設置底色

     */

    private function createImage() {

        //創(chuàng)建圖像

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

        //創(chuàng)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);

    }

    /**

     * 設置干擾元素

     */

    private function setDisturb() {

        //設置干擾點

        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);

        }

        //設置干擾線

        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);

        }

        //創(chuàng)建邊框色

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

        //畫邊框

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

    }

    /**

     * 產(chǎn)生并繪制驗證碼

     */

    private function setCaptcha() {

        $str = '23456789ABCDEFGHJKLMNPQRSTUVWXYZ';

        //生成驗證碼字符

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

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

        }

        //繪制驗證碼

        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);

        }

    }

    /*

     * 輸出圖像,驗證碼保存到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!");

        }

        //將驗證碼信息保存到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：

<?php

 class ValidationCode {

 private $width;

 private $height;

 private $codeNum;

 private $image;  //圖像資源

 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;

  }

 }

 //通過訪問該方法向瀏覽器中輸出圖像

 function showImage($fontFace=""){

  //第一步：創(chuàng)建圖像背景

  $this->createImage();

  //第二步：設置干擾元素

  $this->setDisturbColor();

  //第三步：向圖像中隨機畫出文本

  $this->outputText($fontFace);

  //第四步：輸出圖像

  $this->outputImage();

 }

 //通過調(diào)用該方法獲取隨機創(chuàng)建的驗證碼字符串

 function getCheckCode(){

  return $this->checkCode;

 }

 private function createImage(){

  //創(chuàng)建圖像資源

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

  //隨機背景色

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

  //為背景添充顏色

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

  //設置邊框顏色

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

  //畫出矩形邊框

  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(){

//這里主要產(chǎn)生隨機碼，從2開始是為了區(qū)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不支持圖像創(chuàng)建");

  }

 }

 function __destruct(){

  imagedestroy($this->image);

 }

 }

使用如下：

測試，調(diào)用驗證碼類

code.php

<?php

session_start();

include "validationcode.class.php";

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

$code->showImage();  //輸出到頁面中供 注冊或登錄使用

$_SESSION["code"]=$code->getCheckCode(); //將驗證碼保存到服務器中