spam_image.inc.php

太烦了

<?php
   class SecurityImage {
      var $oImage;
      var $iWidth;
      var $iHeight;
      var $iNumChars;
      var $iNumLines;
      var $iSpacing;
      var $sCode;

      function SecurityImage($iWidth = 150, $iHeight = 30, $iNumChars = 8, $iNumLines = 30) {
         // get parameters
         $this->iWidth = $iWidth;
         $this->iHeight = $iHeight;
         $this->iNumChars = $iNumChars;
         $this->iNumLines = $iNumLines;

         // create new image
         $this->oImage = imagecreate($iWidth, $iHeight);

         // allocate background colour
         $this->oImage = imagecolorallocate($this->oImage, 255, 255, 255);

         // calculate spacing between characters based on width of image
         $this->iSpacing = (int)($this->iWidth / $this->iNumChars);
      }

      function DrawLines() {
         for ($i = 0; $i < $this->iNumLines; $i++) {
            $iRandColour = rand(190, 250);
            $iLineColour = imagecolorallocate($this->oImage, $iRandColour, $iRandColour, $iRandColour);
            imageline($this->oImage, rand(0, $this->iWidth), rand(0, $this->iHeight), rand(0, $this->iWidth), rand(0, $this->iHeight), $iLineColour);
         }
      }

      function GenerateCode() {
         // reset code
         $this->sCode = '';

         // loop through and generate the code letter by letter
         for ($i = 0; $i < $this->iNumChars; $i++) {
            // select random character and add to code string
			// $this->sCode .= chr(rand(65, 90));

            /********************************************/
            /* alternatively replace the line above     */
            /* with the following code to enable        */
            /* support for arbitrary characters         */
            /********************************************/

            // characters to use
			$aChars = array('A','B','C','D','E','F','G','H','I','J', 'K','L','M','N','P','Q','R','S','T','U','V','W','X','Y','Z','1','2','3','4','5','6','7','8','9');

            // get number of characters
            $iTotal = count($aChars) - 1;

            // get random index
            $iIndex = rand(0, $iTotal);

            // add selected character to code string
            $this->sCode .= $aChars[$iIndex];

            /********************************************/
            /* End of optional code                     */
            /********************************************/
         }
      }

      function DrawCharacters() {
         // loop through and write out selected number of characters
         for ($i = 0; $i < strlen($this->sCode); $i++) {
            // select random font
            $iCurrentFont = rand(1, 5);

            // select random greyscale colour
            $iRandColour = rand(0, 255);
            $iTextColour = imagecolorallocate($this->oImage, $iRandColour, $iRandColour, $iRandColour);

            // write text to image
            imagestring($this->oImage, $iCurrentFont, $this->iSpacing / 3 + $i * $this->iSpacing, ($this->iHeight - imagefontheight($iCurrentFont)) / 2, $this->sCode[$i], $iTextColour);
         }
      }

      function Create($sFilename = '') {
         // check for existance of GD GIF library
         if (!function_exists('imagegif')) {
            return false;
         }

         $this->DrawLines();
         $this->GenerateCode();
         $this->DrawCharacters();

         // write out image to file or browser
         if ($sFilename != '') {
            // write stream to file
            imagegif($this->oImage, $sFilename);
         } else {
            // tell browser that data is gif
            header('Content-type: image/gif');

            // write stream to browser
            imagegif($this->oImage);
         }

         // free memory used in creating image
         imagedestroy($this->oImage);

         return true;
      }

      function GetCode() {
         return $this->sCode;
      }
   }
?>