php生成带干扰的验证码程序

这里介绍了一款安全性比较高的验证生成程序，可以带干扰线等内容，可以有效的防止用户用程序识别验证码的难度了。

代码如下

复制代码

/*  * Created on 2011-3-11  * Programmer : xiaoyao, QQ:1045195056  验证通过判断输入值与$_SESSION['check_pic']值  */ session_start();  function RandAscii($number){//$number产生数字和字母个数 $arr=array('0','1','2','3','4','5','6','7','8','9', 'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','w','v','u','x','y','z'); for ($i=1;$i { $rand= $rand.$arr[rand(0,35)]; } return $rand; }  $rand=RandAscii(4); $_SESSION['check_pic']=$rand;//随机产生的四个数赋值session中，用于验证。 $x=80; $y=24;  $im=imagecreatetruecolor($x,$y);//创建图片 $bg=imagecolorallocate($im,255,255,255);//设置颜色背景 imagefill( $im,0,0,$bg); $wh=imagecolorallocate($im,255,255,0); $grey=imagecolorallocate($im,128,128,128); $yellow=imagecolorallocate($im,255,255,0); $red=imagecolorallocate($im,0,255,0); $foregroundArr = array(imagecolorallocate($im, rand(0, 20), rand(0, 20), rand(0, 20)),   imagecolorallocate($im, rand(0, 20), rand(0, 10), rand(245, 255)),   imagecolorallocate($im, rand(245, 255), rand(0, 20), rand(0, 10)),   imagecolorallocate($im, rand(245, 255), rand(0, 20), rand(245, 255))  );//字颜色数组  //画边框  $border = imagecolorallocate($im, 133, 153, 193);  imagerectangle($im, 0, 0, $x - 1, $y - 1, $border); for($i=0;$i imageline($im,rand(0,60),2,rand(0,60),20,$yellow); } for($j=0;$j  imagesetpixel($im,rand()%76,rand()%20,$red); } //imagestring($im,6,15,8,$rand,$wh);//字体大小1-5 imagettftext($im, 14,rand(30, -30), 5, rand(15, 18) ,$foregroundArr[rand(0,3)], 'C:WindowsFontsArial.ttf',$rand[0]); imagettftext($im, 14,rand(50, -50), 24, rand(15, 18),$foregroundArr[rand(0,3)], 'C:WindowsFontsArial.ttf',$rand[1]); imagettftext($im, 14,rand(50, -50), 43, rand(15, 18) ,$foregroundArr[rand(0,3)], 'C:WindowsFontsArial.ttf',$rand[2]); imagettftext($im, 14,rand(30, -30), 62, rand(15, 18),$foregroundArr[rand(0,3)], 'C:WindowsFontsArial.ttf',$rand[3]); header("Content-type: image/jpeg");//输出图片 imagejpeg($im); imagedestroy($im); ?>

调用方法

代码如下	复制代码
/*  * Created on 2011-3-11  * Programmer : xiaoyao, QQ:1045195056  验证通过判断输入值与$_SESSION['check_pic']值  */ session_start();//开启session if(isset($_POST['check'])) { if($_POST['check'])  { if($_POST['check']==$_SESSION['check_pic'])  {  echo " 验证码正确".$_SESSION['check_pic'];  } else  {  echo " 验证码错误".$_SESSION['check_pic'];  } } } ?>