CodeIgniter框架验证码类库文件与用法示例

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：

<?php
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('<img id=\"img_authcode\" src=\"' + img_src + math.random() + '\" style=\"cursor:hand;\" onclick=\"this.src=img_src + math.random();\" alt=\"点击更换图片\">');";
 }
 /**
  * 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：

<?php echo form_open('c=admin&m=captcha');?>
<input type="text" name="gd_pic" />
<img src="<?php echo base_url('?c=admin&m=show_captcha');?>" ><br>
<input type="submit" name="submit" value="验证" />
<?php echo form_close();?>

ok. 一切结束，终于正常运行了。

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