php實現的加減法驗證碼代碼

 這篇文章主要介紹了php實現的加減法驗證碼代碼，可以使用10以內的加減法生成圖片,需要的朋友可以參考下

 代碼如下: <?php /*圖片驗證碼文件，加減計算方式*/   class ImageCode{    private $Jiashu  = 0;        //加數或者減數  private $JianShu = 0;        //被加數或者被減數  private $YunSuan = '';       //運算符  private $DeShu   = 0;        //得數  private $String  = '';       //字符串樣式  private $Img;                //圖片對象  private $Width   = 100;      //圖片寬度  private $Height  = 50;       //圖片高度  private $Ttf     = 'Num.ttf';//字體文件  private $Session = 'code';   //Session變量    private function JiaShu(){   header('Content-type:image/png');   $this -> Jiashu  = rand(1, 10);   $this -> JianShu = rand(1, 10);   $this -> YunSuan= $this -> Jiashu > $this -> JianShu ? '-' : '+';   $this -> DeShu   = $this -> Jiashu > $this -> JianShu ? $this -> Jiashu - $this -> JianShu : $this -> Jiashu + $this -> JianShu;  }    public function Show( $W = 100, $H = 50, $T = 'Num.ttf', $Code = 'code' ){   $this -> JiaShu();   $this -> String = $this -> Jiashu . $this -> YunSuan . $this -> JianShu . '= ? ';   $this -> Width  = $W;   $this -> Height = $H;   $this -> Ttf    = $T;   $this -> Session= $Code;   session_start();   $_SESSION[$this -> Session] = $this -> DeShu;   $this -> Images();  }    private function Images(){   $this -> Img = imagecreate($this -> Width, $this -> Height);   $background_color = imagecolorallocate ($this -> Img, 255, 255, 255);   imagecolortransparent($this -> Img, $background_color);         imagettftext($this -> Img, 14, 0, 1, 20, imagecolorallocate ($this -> Img, 0, 0, 0), $this -> Ttf, $this -> String );   $this -> EchoImages();  }    private function EchoImages(){   imagepng($this -> Img);   imagedestroy($this -> Img);  }   }   $ImageCode = new ImageCode; $ImageCode -> Show(130, 35, 'Num.ttf', 'code');