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PHP verification code generation program code_PHP tutorial

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2016-07-13 17:11:02768browse

This article will introduce you to the program that uses session storage and gd library to generate verification codes. At the same time, some interference elements will be added, so that you can simply prevent machine registration. Let me introduce it to you.

PHP verification code and image generation program, using session recognition, slightly improved the PHP verification code currently circulating on the Internet, adding miscellaneous dots, randomly displaying digital colors, and controlling 4-digit display; without further ado, The procedure is as follows, please share it.

Create a new yz.php verification code generation file:

Note: The following code requires opening the GD library of php, modifying the configuration of the php.in file, and canceling the semicolon before the commented out line: extension=php_gd2.dll.

 代码如下 复制代码

   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($i=0;$i<$this->disturbColorNum;$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;$i<$this->codeNum;$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;$i<$this->codeNum;$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();
   }

?>


Go to the specific call place and use this form: That's it; when verifying, verify the value of session: $_SESSION['VCODE'] That's it. You can also slightly improve the above code and change it to the form of adding two numbers

www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/629629.htmlTechArticleThis article introduces you to the use of session storage and gd library to generate verification codes, while adding some interfering elements. , so that you can easily prevent machine registration. Let me tell you...
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