PHP+Ajax远程图片抓取器下载的例子

<?php
header('Content-Type; text/json; charset=utf-8');
$Single=$_GET['Single'];
$more=$_GET['more'];
$TargetUrl=$_POST['TargetUrl'];
$Save=$_POST['Save'];
//判断是抓取单个图片还是多个图片
if ($Single=='Single') {
 $ImageCatch=new ImageCatch($TargetUrl,$Save);
 $ImageCatch->S();
}else if ($more=='more') {
 $ImageCatch=new ImageCatch($TargetUrl,$Save);
 $ImageCatch->M();
}
//图片抓取类
class ImageCatch {
 private $TargetUrl;  //目标地址
 private $Save;  //保存地址
 private $FileName; //文件名称及路径
 private $Type;  //文件类型
 private $Size;  //文件大小
 //构造函数
 public function __construct($TargetUrl,$Save) {
  $this->TargetUrl=str_replace("'",'',$TargetUrl);   //去掉单引号
  $this->Save=$Save;
 }
 //CSS样式表中图片抓取方法
 public function CSS() {
  $content=@file_get_contents($this->TargetUrl);
  //CSS图片过滤
  preg_match_all('/<link.+href="?(.*?.css)"?.+>/i',$content,$css);
  $css[1]=array_unique($css[1]);//移除重复的值
  $match2=array();
  if (count($css[1])>0) {
   foreach($css[1] as $val) {
    if (!preg_match('/^(https?://)/i',$val)) {
     $val=$this->TargetUrl.'/'.$val;
     $csscontent=@file_get_contents($val);
    }else {
     $csscontent=@file_get_contents($val);
    }
    //匹配图片URL地址
    preg_match_all('/url((.*))/i',$csscontent,$cssimg);
    $cssimg[1]=array_unique($cssimg[1]);//移除重复的值
   }   
   foreach($cssimg[1] as $val) {
    //去除 " ) 字符
    $val=preg_replace(array('/"|)/'),'',$val);
    //去除../字符
    $val=str_replace('../','',$val);
    //检查是否是http://开头，如果不是则加上要抓取的网址
    if (!preg_match('/^(https?://)/i',$val)) {
     array_push($match2,$this->TargetUrl.'/'.$val);
    }else {
     array_push($match2,$val);
    }
   }
   return $match2;
  }
 }
 //计算并返回图片数量及地址
 public function M() {
  $content=@file_get_contents($this->TargetUrl);
  //网页图片过滤
  $str='/<img.+src="?(.+.(jpg|gif|bmp|bnp|png))"?.+>/i';
  preg_match_all($str,$content,$res);
  if ($res[1]) {
   $res[1]=array_unique($res[1]);//移除重复的值
   $httpstr='/^(https?://)/i';
   $match=array();
   foreach($res[1] as $val) {
    if (!preg_match($httpstr,$val)) {
     array_push($match,$this->TargetUrl.'/'.$val);
    }else {
     array_push($match,$val);
    }
   }
   $cssimg=$this->CSS();
   //扫描出css文件图片的总数与网页图片相加得到总数
   $total=array("total"=>count($match)+count($cssimg));
   $result=array_merge($total,$match,$cssimg);
   //返回JSON数据
   echo json_encode($result);
  }else {
   $res=array('no');
   echo json_encode($res);
  }
  exit;
 }
 //抓取并保存图片
 public function S() {
  $this->Type=substr(strrchr($this->TargetUrl,'.'),1);
  $this->FileName=$this->Save.'/'.substr(strrchr($this->TargetUrl,'/'),1);
  $this->imageType();
  $content=@file_get_contents($this->TargetUrl);
  $this->imageDir();
  if (!@file_put_contents($this->FileName,$content,FILE_USE_INCLUDE_PATH)) {
   @unlink($this->FileName);
   exit('{"status":"没有找到 '.$this->TargetUrl.' 图片"}');
  }else {
   $this->imageSize();
   exit('{"status":"ok","FileSave":"'.$this->FileName.'","FileSize":"'.$this->Size.'"}');
  }
 }
 //新建目录
 private function imageDir() {
  if (!@file_exists($this->Save)) {
   if (!@mkdir($this->Save,0700)) {
    exit('{"status":"新建保存目录失败"}');
   }
  }
 }
 //文件类型判断
 private function imageType() {
  $typeArr=array('jpg','png','gif','zip','rar');
  if (!in_array($this->Type,$typeArr)) {
   exit('{"status":"要执行抓取的文件扩展名有错误,'.$this->TargetUrl.'"}');
  }
 }
 //文件大小检测
 private function imageSize() {
  if (file_exists($this->FileName)) {
   $this->Size=filesize($this->FileName);
   if ($this->Size>1024*1024*1024) {
    $this->Size=round($this->Size/1024/1024/1024,2).' GB';
   }else if ($this->Size>1024*1024) {
    $this->Size=round($this->Size/1024/1024,2).' MB';
   }else if ($this->Size>1024) {
    $this->Size=$this->Size/1024;
    $this->Size=ceil($this->Size).'KB';
   }else {
    $this->Size=$this->Size.'bit';
   }
  }else {
   return '未找到文件';
  }
 }
}
?>