/**

* @file

* @version  1.0

* @author   网海浪子

* @date  2006-3-30

* @email sxf02615@163.com

* @brief    验证码文件类

*

*/

?>

class CCheckCodeFile

{

//验证码位数

private $mCheckCodeNum  = 4;

//产生的验证码

private $mCheckCode   = '';

//验证码的图片

private $mCheckImage  = '';

//干扰像素

private $mDisturbColor  = '';

//验证码的图片宽度

private $mCheckImageWidth = '80';

//验证码的图片宽度

private $mCheckImageHeight  = '20';

/**

*

* @brief  输出头

*

*/

private function OutFileHeader()

{

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

}

/**

*

* @brief  产生验证码

*

*/

private function CreateCheckCode()

{

$this->mCheckCode = strtoupper(substr(md5(rand()),0,$this->mCheckCodeNum));

return $this->mCheckCode;

}

/**

*

* @brief  产生验证码图片

*

*/

private function CreateImage()

{

$this->mCheckImage = @imagecreate ($this->mCheckImageWidth,$this->mCheckImageHeight);

imagecolorallocate ($this->mCheckImage, 200, 200, 200);

return $this->mCheckImage;

}

/**

*

* @brief  设置图片的干扰像素

*

*/

private function SetDisturbColor()

{

for ($i=0;$i<=128;$i++)

{

$this->mDisturbColor = imagecolorallocate ($this->mCheckImage, rand(0,255), rand(0,255), rand(0,255));

imagesetpixel($this->mCheckImage,rand(2,128),rand(2,38),$this->mDisturbColor);

}

}

/**

*

* @brief  设置验证码图片的大小

*

* @param  $width  宽

*

* @param  $height 高

*

*/

public function SetCheckImageWH($width,$height)

{

if($width==''||$height=='')return false;

$this->mCheckImageWidth  = $width;

$this->mCheckImageHeight = $height;

return true;

}

/**

*

* @brief  在验证码图片上逐个画上验证码

*

*/

private function WriteCheckCodeToImage()

{

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

{

$bg_color = imagecolorallocate ($this->mCheckImage, rand(0,255), rand(0,128), rand(0,255));

$x = floor($this->mCheckImageWidth/$this->mCheckCodeNum)*$i;

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

imagechar ($this->mCheckImage, 5, $x, $y, $this->mCheckCode[$i], $bg_color);

}

}

/**

*

* @brief  输出验证码图片

*

*/

public function OutCheckImage()

{

$this ->OutFileHeader();

$this ->CreateCheckCode();

$this ->CreateImage();

$this ->SetDisturbColor();

$this ->WriteCheckCodeToImage();

imagepng($this->mCheckImage);

imagedestroy($this->mCheckImage);

}

}

$c_check_code_image = new CCheckCodeFile();

//$c_check_code_image ->SetCheckImageWH(100,50);//设置显示验证码图片的尺寸

$c_check_code_image ->OutCheckImage();

?>

itlearner注：能产生随机的英文字母和数字，不错!