class ValidationCode

{

//属性

private $width;

private $height;

private $codeNum;

private $image;

private $disturbColorNum; //干扰元素数目

private $checkCode;

function __construct($width=80,$height=20,$codeNum=4)

{

$this->width=$width;

$this->height=$height;

$this->codeNum=$codeNum;

$number=floor($width*$height/15);

if($number>240-$codeNum)

{

$this->disturbColorNum=240-$codeNum;

}else

{

$this->disturbColorNum=$number;

}

$this->checkCode=$this->createCheckcode();

}

function getCheckCode()

{

return $this->checkCode;

}

private function createImage(){

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

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

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

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

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

}

private function setDisturbColor(){

for($i=0;$idisturbColorNum;$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(0,255),rand(0,255),rand(0,255));

imagearc($this->image,rand(-10,$this->width),rand(-10,$this->height),rand(30,300),rand(20,300),55,44,$color);

}

}

private function outputText($fontFace=""){

for($i=0;$icodeNum;$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+5;

$y=rand(0,$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,$this->height-8);

imagettftext($this->image,$fontsize,rand(-45,45),$x,$y,$fontcolor,$fontFace,$this->checkCode{$i});

}

}

}

private function createCheckCode(){

$code="23456789abcdefghijkmnpqrstuvwrst";

$str="";

for($i=0;$icodeNum;$i++)

{

$char=$code{rand(0,strlen($code)-1)};

$str.=$char;

}

return $str;

}

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不支持图片验证码");

}

}

//通过该方法向浏览器输出图像

function showImage($fontFace="")

{

//创建图像背景

$this->createImage();

//设置干扰元素

$this->setDisturbColor();

//向图像中随机画出文本

$this->outputText($fontFace);

//输出图像

$this->outputImage();

}

function __destruct()

{

imagedestroy($this->image);

}

}

function checklogin(){

if(empty($_POST['name']))

die( '用户名不能为空');

if(empty($_POST['password']))

die("密码不能为空");

if($_SESSION['code']!=$_POST['vertify'])

die("验证码输入不正确".$_SESSION['code']);

$username=$_POST['name'];

$password=md5($_POST['password']);

//检查是否存在

conndb($username,$password);

}

function conndb($name="",$ps=""){

$conn=mysql_connect('localhost','root','123456');

if(!$conn) die("数据库连接失败".mysql_error());

mysql_select_db('5kan',$conn) or die('选择数据库失败'.mysql_error());

mysql_set_charset('utf8',$conn);

$sql="select id from k_user where username='{$name}' and password='{$ps}'";

$result=mysql_query($sql) or die("SQL语句错误".mysql_error());

if(mysql_num_rows($result)>0) die("登录成功");

else die("用户名或者密码错误");

mysql_close($conn);

}

session_start();

if(!isset($_POST['randnum']))

{

$code=new ValidationCode(120,20,4);

$code->showImage("comicbd.ttf"); //显示在页面

$_SESSION['code']=$code->getCheckCode();//保存在服务器中

}

else

{

checklogin();

}

?>