php5验证码类(简易实用型)

PHP验证码类的代码。

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