php之session实战

小项目

验证码session使用

 public static function create(){
        // 配置
        $config = self::_getCodeConfig();
        //创建画布
        $image = imagecreatetruecolor($config['width'],$config['height']);
        //背景颜色
        $bgcolor=imagecolorallocate($image,255,255,255);
        imagefill($image,0,0,$bgcolor);
        $captch_code = '';//存储验证码
        $captchCodeArr = str_split($config['codeStr']);
        //随机选取4个候选字符
        for($i=0;$i<$config['codeCount'];$i++){
            $fontsize = $config['fontsize'];
            $fontcolor=imagecolorallocate($image,rand(0,120),rand(0,120),rand(0,120));//随机颜色
            $fontcontent = $captchCodeArr[rand(0,strlen($config['codeStr'])-1)];
            $captch_code.=$fontcontent;
            $_x = $config['width']/$config['codeCount'];
            $x=($i*(int)$_x)+rand(5,10);   //随机坐标
            $y=rand(5,10);
            imagestring($image,$fontsize,$x,$y,$fontcontent,$fontcolor);    // 水平地画一行字符串
            //imagefttext($im, $size, 2, $size * (0.5 + $i * 1.1), $size * 1.2, $font, Env::get('root_path') . 'public/static/fonts/COOPBL.TTF', $authnum);
        }
        session_start();
        $_SESSION['code']=$captch_code;
        //增加干扰点
        if($config['disturbPoint']){
            for($i=0;$i<$config['pointCount'];$i++){
                $pointcolor=imagecolorallocate($image,rand(50,200),rand(50,200),rand(50,200));
                imagesetpixel($image,rand(1,99),rand(1,29),$pointcolor);
            }
        }
        //增加干扰线
        if($config['disturbLine']){
            for($i=0;$i<$config['lineCount'];$i++){
                $linecolor=imagecolorallocate($image,rand(80,280),rand(80,220),rand(80,220));
                imageline($image,rand(1,99),rand(1,29),rand(1,99),rand(1,29),$linecolor);
            }
        }
        //输出格式
        header('Content-Type:image/png');
        imagepng($image);
        //销毁图片
        imagedestroy($image);
    }