本文实例讲述了CodeIgniter框架验证码类库文件与用法。分享给大家供大家参考，具体如下：
折腾了我四五个小时，终于，ci的验证码类库成功的整出来了。
下面请看源码：
在application/libraries建立Authcode.php文件，代码如下：
class Authcode
{
var $CI;
var $fontPath;//字体路径
var $image;
var $charLen = 4; //生成几位验证码
var $arrChr = array();//验证码字符
var $width = 83; //图片宽
var $height = 24; //图片高
var $bgcolor = "#ffffff"; //背景色
var $showNoisePix = true; //生成杂点
var $noiseNumPix = 80; //生成杂点数量
var $showNoiseLine = true; //生成杂线
var $noiseNumLine = 2; //生成杂线数量
var $showBorder = true; //边框，当杂点、线一起作用的时候，边框容易受干扰
var $borderColor = "#000000";
function Authcode()
{
$this->CI = & get_instance();
$this->fontPath = realpath(dirname(__FILE__) . '/fonts/'); //字体文件
//$this->arrChr = array_merge(range(1, 9) , range('A', 'Z'));//数字字母验证码
//$this->arrChr = range('A', 'Z');//纯字母验证码
$this->arrChr = range(0, 9);//纯数字验证码
}
/**
* 显示验证码
*
*/
function show()
{
$this->image = imageCreate($this->width, $this->height);
$this->back = $this->getColor($this->bgcolor);
imageFilledRectangle($this->image, 0, 0, $this->width, $this->height, $this->back);
$size = $this->width / $this->charLen - 4;
if ($size > $this->height) {
$size = $this->height;
}
$left = ($this->width - $this->charLen * ($size + $size / 10)) / $size + 5;
$code = '';
for($i = 0; $i < $this->charLen; $i ++) {
$randKey = rand(0, count($this->arrChr) - 1);
$randText = $this->arrChr[$randKey];
$code .= $randText;
$textColor = imageColorAllocate($this->image, rand(0, 100), rand(0, 100), rand(0, 100));
$font = $this->fontPath . '/' . rand(1, 5) . ".ttf";
$randsize = rand($size - $size / 10, $size + $size / 10);
$location = $left + ($i * $size + $size / 10);
@imagettftext($this->image, $randsize, rand(- 18, 18), $location, rand($size - $size / 10, $size + $size / 10) + 2, $textColor, $font, $randText);
}
if ($this->showNoisePix == true) {
$this->setNoisePix();
}
if ($this->showNoiseLine == true) {
$this->setNoiseLine();
}
if ($this->showBorder == true) {
$this->borderColor = $this->getColor($this->borderColor);
imageRectangle($this->image, 0, 0, $this->width - 1, $this->height - 1, $this->borderColor);
}
$this->CI->session->set_userdata('auth_code', $code);
ob_clean();
header("Content-type: image/jpeg");
imagejpeg($this->image);
imagedestroy($this->image);
}
/**
* 显示验证码的JS调用
*
*/
function showScript()
{
//显示验证码
echo "var img_src = '/imgauthcode/show/?';\n";
echo "document.writeln('');";
}
/**
* 检查验证码是否正确
*
* @param string $auth_code
* @return bool
*/
function check($auth_code = null)
{
return ($this->CI->session->userdata('auth_code') && $auth_code) ? ($this->CI->session->userdata('auth_code') === $auth_code) : false;
}
function getColor($color)
{
$color = eregi_replace("^#", "", $color);
$r = $color[0] . $color[1];
$r = hexdec($r);
$b = $color[2] . $color[3];
$b = hexdec($b);
$g = $color[4] . $color[5];
$g = hexdec($g);
$color = imagecolorallocate($this->image, $r, $b, $g);
return $color;
}
function setNoisePix()
{
for($i = 0; $i < $this->noiseNumPix; $i ++) {
$randColor = imageColorAllocate($this->image, rand(0, 255), rand(0, 255), rand(0, 255));
imageSetPixel($this->image, rand(0, $this->width), rand(0, $this->height), $randColor);
}
}
function setNoiseLine()
{
for($i = 0; $i < $this->noiseNumLine; $i ++) {
$randColor = imageColorAllocate($this->image, rand(0, 255), rand(0, 255), rand(0, 255));
imageline($this->image, rand(1, $this->width), rand(1, $this->height), rand(1, $this->width), rand(1, $this->height), $randColor);
}
}
}
Authcode.php代码结束
在Controller中，有个admin类，其中有两个方法：
Class Admin extends CI_Controller{
function __construct()
{
parent::__construct();
$this->load->library('Authcode');
}
function captcha(){
if($_POST){
if ($this->authcode->check($this->input->post('gd_pic'))) {
echo "right";
} else {
echo '验证码不正确，请重新输入';
}
}else{
$this->load->view('demo');
}
}
function show_captcha(){ //此方法用于显示验证码图片，归一个view中的img的src调用
$this->authcode->show();
}
}
下面是在视图view中创建一个demo.php了，代码如下：
OK. 一切结束，终于正常运行了。
希望本文所述对大家基于CodeIgniter框架的PHP程序设计有所帮助。
