PHP生成加减算法方式的验证码

PHP培训

<?php namespace mobilecomponents;/**  * @author fenghuo  *  * 改造的加减法验证类  * 使用示例 VerifyCode::get(1,2);  * 验证示例 VerifyCode::check($code);  */ class VerifyCode {  /**  * php验证码  */  public static function get($one,$two,$prefix = "", $font_size = 28)  {  //文件头...  ob_get_clean(); header("Content-type: image/png;charset=utf-8;");  //创建真彩色白纸  $width = $font_size*5;  $height = $font_size+1;  $im = @imagecreatetruecolor($width, $height) or die("建立图像失败");  //获取背景颜色  $background_color = imagecolorallocate($im, 255, 255, 255);  //填充背景颜色  imagefill($im, 0, 0, $background_color);  //获取边框颜色  $border_color = imagecolorallocate($im, 200, 200, 200);  //画矩形，边框颜色200,200,200  imagerectangle($im,0,0,$width - 1, $height - 1,$border_color);  //逐行炫耀背景，全屏用1或0  for($i = 2;$i < $height - 2;$i++) {  //获取随机淡色  $line_color = imagecolorallocate($im, rand(200,255), rand(200,255), rand(200,255));  //画线  imageline($im, 2, $i, $width - 1, $i, $line_color);  }  //设置印上去的文字  $firstNum = $one;  $secondNum = $two;  $actionStr = $firstNum > $secondNum ? "-" : "+";  //获取第1个随机文字  $imstr[0]["s"] = $firstNum;  $imstr[0]["x"] = rand(2, 5);  $imstr[0]["y"] = rand(1, 4);  //获取第2个随机文字  $imstr[1]["s"] = $actionStr;  $imstr[1]["x"] = $imstr[0]["x"] + $font_size - 1 + rand(0, 1);  $imstr[1]["y"] = rand(1,5);  //获取第3个随机文字  $imstr[2]["s"] = $secondNum;  $imstr[2]["x"] = $imstr[1]["x"] + $font_size - 1 + rand(0, 1);  $imstr[2]["y"] = rand(1, 5);  //获取第3个随机文字  $imstr[3]["s"] = "=";  $imstr[3]["x"] = $imstr[2]["x"] + $font_size - 1 + rand(0, 1);  $imstr[3]["y"] = 3;  //获取第3个随机文字  $imstr[4]["s"] = "?";  $imstr[4]["x"] = $imstr[3]["x"] + $font_size - 1 + rand(0, 1);  $imstr[4]["y"] = 3;  //文字  $text = "";  //写入随机字串  for($i = 0; $i < 5; $i++) {  //获取随机较深颜色  $text_color = imagecolorallocate($im, rand(50, 180), rand(50, 180), rand(50, 180));  $text .= $imstr[$i]["s"];  //画文字  imagechar($im, $font_size, $imstr[$i]["x"], $imstr[$i]["y"], $imstr[$i]["s"], $text_color);  }  session_start(); $_SESSION[$prefix."verifycode"] = $firstNum > $secondNum ? ($firstNum - $secondNum) : ($firstNum + $secondNum);  //显示图片  ImagePng($im);  //销毁图片  ImageDestroy($im);  }  public static function check($code)  {  if(trim($_SESSION[$prefix."verifycode"]) == trim($code)) {  return true;  } else {  return false;  }  } }