PHP中驗證碼類及使用方法

 

備注:將公共頁面加入session_start();

 

<?php

session_start();

ini_set('display_errors', 'Off');

class CCheckCodeFile

{

       //驗證碼位數 www.2cto.com

 

       var $mCheckCodeNum  = 4;

 

       //產生的驗證碼

       var $mCheckCode   = '';

 

       //驗證碼的圖片

       var $mCheckImage  = '';

 

       //干擾像素

       var $mDisturbColor  = '';

 

       //驗證碼的圖片寬度

       var $mCheckImageWidth = '80';

 

       //驗證碼的圖片寬度

       var $mCheckImageHeight  = '20';

 

       //輸出頭

       function OutFileHeader()

       {

              header ("Content-type: image/png");

       }

 

       //產生驗證碼

       function CreateCheckCode()

       {

              //$this->mCheckCode = strtoupper(substr(md5(rand()),0,$this->mCheckCodeNum));

              $this->mCheckCode = strtoupper(substr(rand(0,9999999999),0,$this->mCheckCodeNum));

              session_cache_expire(60);

              session_start();

              $_SESSION["code_str"] = $this->mCheckCode;

              return $this->mCheckCode;

       }

 

       //產生驗證碼圖片

       function CreateImage()

       {

              $this->mCheckImage = @imagecreate ($this->mCheckImageWidth,$this->mCheckImageHeight);

              imagecolorallocate ($this->mCheckImage, 255, 255, 255);

              return $this->mCheckImage;

       }

 

       //設置圖片的干擾像素

       function SetDisturbColor()

       {

              for ($i=0;$i<=128;$i++)

              {

                     $this->mDisturbColor = imagecolorallocate ($this->mCheckImage, rand(0,255), rand(0,255), rand(0,255));

                     imagesetpixel($this->mCheckImage,rand(1,100),rand(1,100),$this->mDisturbColor);

              }

       }

 

       //設置驗證碼圖片的大小\寬\高

       function SetCheckImageWH($width,$height)

       {

              if($width==''||$height=='')return false;

              $this->mCheckImageWidth  = $width;

              $this->mCheckImageHeight = $height;

              return true;

       }

 

       //在驗證碼圖片上逐個畫上驗證碼

       function WriteCheckCodeToImage()

       {

              for ($i=0;$i<=$this->mCheckCodeNum;$i++)

              {

                     $bg_color = imagecolorallocate ($this->mCheckImage, rand(0,255), rand(0,255), rand(0,255));

                     $x = floor($this->mCheckImageWidth/$this->mCheckCodeNum)*$i;

                     $y = rand(0,$this->mCheckImageHeight-15);

                     imagechar ($this->mCheckImage, 5, $x, $y, $this->mCheckCode[$i], $bg_color);

              }

       }

 

       //輸出驗證碼圖片

       function OutCheckImage()

       {

              $this ->OutFileHeader();

              $this ->CreateCheckCode();

              $this ->CreateImage();

              $this ->SetDisturbColor();

              $this ->WriteCheckCodeToImage();

              imagepng($this->mCheckImage);

              imagedestroy($this->mCheckImage);

       }

}

 

$c_check_code_image = new CCheckCodeFile();

//$c_check_code_image ->SetCheckImageWH(100,50);//設置顯示驗證碼圖片的尺寸

$c_check_code_image->OutCheckImage();

?>

 

 

 

使用方法:

<tr>

      <td align="center" valign="middle">驗證碼</td>

      <td align="center" valign="middle"><input name="number" type="text" style="width:80px;">

      <img src="code.php" id="yzm" onclick="this.src='code.php?abc='+Math.random()" alt="圖片看不清？點擊重新得到驗證碼" style="cursor:hand;" />

</td>

    </tr>

 

 

驗證是否正確

 

session_start();

 

  if($_POST["number"] == $_SESSION["code_str"]){

  //      echo("驗證碼正確");

  }else{

        echo "

 

                     <script>

 

                            var s=10;

 

                            function ok()

 

                            {

 

                            s--;

 

                            document.getElementById('tips').innerHTML=s;

 

                            if(s==0)

 

                            {

 

                            clearTimeout(t);

 

                            history.go(-1);

 

                            }

 

                            }

 

                            var t=setInterval('ok()',1000);

 

                     </script>

 

" . "請輸入的驗證碼,請重新輸入<span id='tips'></span>秒之後，將為您跳轉到<a href=\"javascript:history.go(-1)\">上一頁</a>";

  }

 

摘自 http://itsafe.org/?p=384