<?phpclass class_authcode{    public  $authcode   = ‘‘; //验证码    private $width      = ‘‘; //验证码图片宽    private $height     = ‘‘; //验证码图片高    private $len        = ‘‘; //验证码长度    private $tilt       = array(-30,30);//验证码倾斜角度    private $font       = ‘AlteHaasGroteskBold.ttf‘;//字体文件    private $str        = ‘‘; //验证码基    private $im         = ‘‘; //生成图片的句柄    //构造函数    function __construct($width=100,$heigh=30,$len=4) {        $this->width    = $width;        $this->height   = $heigh;        $this->len      = $len;        $this->str      = ‘ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz‘;        $str_len = strlen($this->str)-1;        for ($i=0; $i<$len; $i++) {            $this->authcode .= $this->str[rand(0,$str_len)];        }    }    //生成验证码图片    private function imagecreate(){        $this->im = imagecreatetruecolor($this->width,$this->height);    }    //干扰颜色    private function ext_color() {        return imagecolorallocate($this->im,rand(50, 180),rand(50, 180),rand(50, 180));    }    //生成干扰点    private function ext_point() {        for ($i=0; $i<$this->width*2; $i++) {            imagesetpixel($this->im,rand(1,$this->width-1),rand(1,$this->height-1),$this->ext_color());        }    }    //生成干扰线    private function ext_line() {        for ($i=0; $i<$this->len; $i++) {            $x1 = rand(1,$this->width-1);            $y1 = rand(1,$this->height-1);            $x2 = rand(1,$this->width-1);            $y2 = rand(1,$this->height-1);            imageline($this->im,$x1,$y1,$x2,$y2,$this->ext_color());        }    }    //把验证码写入图片（不能和$this->imgstrfloat()同时使用）    private function imgstr() {        $old_x = 1;        for ($i=0; $i<$this->len; $i++) {            $fontsize = rand(2,5);      //字体大小            $tmp_1 = $fontsize*2.5;            $tmp_2 = $i>0  $tmp_1 : 0;            $y = rand(1,$this->height/2);            $x = rand($old_x+$tmp_2, ($i+1)*($this->width)/$this->len-$tmp_1);            $old_x = $x;            $color = imagecolorallocate($this->im,rand(200, 255),rand(200, 255),rand(200, 255));            imagestring($this->im,$fontsize,$x,$y,$this->authcode[$i],$color);        }    }    //把验证码倾斜写入图片（注意这里不能和$this->imgstr()方法同时使用）    private function imgstrfloat() {        $old_x = 1;        for ($i=0; $i<$this->len; $i++) {            $fontfloat = rand($this->tilt[0],$this->tilt[1]);            $fontsize = rand(10,15);        //字体大小            $tmp_1 = $i>0  $fontsize : 0;            $y = rand($fontsize+2, $this->height-2);            $x = rand($old_x+$tmp_1+2, ($i+1)*($this->width)/$this->len-$fontsize-2);            $old_x = $x;            $color = imagecolorallocate($this->im, rand(200, 255), rand(200, 255), rand(200, 255));            imagettftext($this->im, $fontsize, $fontfloat, $x, $y, $color, $this->font, $this->authcode[$i]);        }    }    //输出验证码图片    function output() {        $this->imagecreate();        $this->imgstr();        //$this->imgstrfloat();        $this->ext_point();        $this->ext_line();        header(‘content-type:image/png‘);        imagepng($this->im);        imagedestroy($this->im);    }}?>

$obj = new class_authcode();//实例化对象，并设置验证码图片的宽、高和验证码的长度$obj->$authcode; //获取验证码$obj->output(); //输出验证码图片