发布一个用PHPfsockopen写的HTTP下载的类_php实例

如果支持打开远程内容的选项的话，实际上php用fopen或file_get_contents都能获得一个网页的内容，但是默认的函数有个不足的地方就是无法获取HTTP头，这在一些特殊的应用中很不方便，如，有一个链接：

http://www.abc.com/showvd.asp?id=18

假如它返回的是一个图片，用默认函数就很难识别，但如果通过HTTP应答头来判断就简单多了，此外如果对方通过 Refer 来防盗链的话，也是无法获取的，用HTTP类就能完美解决这些问题，而且速度也相差无几。


使用方法：

$hd = new DedeHttpDown();
$hd->OpenUrl("http://www.dedecms.com");
echo $hd->GetHtml();
//如果保存为文件则用 $hd->SaveBin("dede.html");
$hd->Close();

获得http请求头用
$hd->GetHead("key")
设置请求头
$hd->SetHead(key,value); (必须在调用 OpenUrl 之前设定)


代码如下:

/* --------------------------------------------------------------------- 
//织梦Http下载类V1.0 
//出自：织梦之旅 http://www.dedecms.com 
//作者: IT柏拉图 
//时间: 2005-11-13 12:39 
//声明: 首发在落伍者网站，转载请保留版权信息 
--------------------------------------------------------------------- */ 
class DedeHttpDown 
{ 
        var $m_url = ""; 
        var $m_urlpath = ""; 
        var $m_scheme = "http"; 
        var $m_host = ""; 
        var $m_port = "80"; 
        var $m_user = ""; 
        var $m_pass = ""; 
        var $m_path = "/"; 
        var $m_query = ""; 
        var $m_fp = ""; 
        var $m_error = ""; 
        var $m_httphead = "" ; 
        var $m_html = ""; 
        var $m_puthead = ""; 
        var $BaseUrlPath = ""; 
        var $HomeUrl = ""; 
        var $JumpCount = 0;//防止多重重定向陷入死循环 
        // 
        //初始化系统 
        // 
        function PrivateInit($url) 
        { 
                        if($url=="") return ; 
                        $urls = ""; 
                        $urls = @parse_url($url); 
                        $this->m_url = $url; 
            if(is_array($urls)) 
            { 
                          $this->m_host = $urls["host"]; 
                          if(!empty($urls["scheme"])) $this->m_scheme = $urls["scheme"]; 

                          if(!empty($urls["user"])){ 
                                        $this->m_user = $urls["user"]; 
                          } 

                          if(!empty($urls["pass"])){ 
                                        $this->m_pass = $urls["pass"]; 
                          } 

                          if(!empty($urls["port"])){ 
                                        $this->m_port = $urls["port"]; 
                          } 

                          if(!empty($urls["path"])) $this->m_path = $urls["path"]; 
                          $this->m_urlpath = $this->m_path; 

                          if(!empty($urls["query"])){ 
                                        $this->m_query = $urls["query"]; 
                                        $this->m_urlpath .= "?".$this->m_query; 
                          } 
                          $this->HomeUrl = $urls["host"]; 
                          $this->BaseUrlPath = $this->HomeUrl.$urls["path"]; 
                          $this->BaseUrlPath = ereg_replace("/([^/]*)\.(.*)$","/",$this->BaseUrlPath); 
                          $this->BaseUrlPath = ereg_replace("/$","",$this->BaseUrlPath); 
                 } 
        } 
        // 
        //打开指定网址 
        // 
        function OpenUrl($url) 
        { 
                //重设各参数 
                $this->m_url = ""; 
                $this->m_urlpath = ""; 
                $this->m_scheme = "http"; 
                $this->m_host = ""; 
                $this->m_port = "80"; 
                $this->m_user = ""; 
                $this->m_pass = ""; 
                $this->m_path = "/"; 
                $this->m_query = ""; 
                $this->m_error = ""; 
                $this->JumpCount = 0; 
                $this->m_httphead = Array() ; 
                //$this->m_puthead = ""; 
                $this->m_html = ""; 
                $this->Close(); 
                //初始化系统 
                $this->PrivateInit($url); 
                $this->PrivateStartSession(); 
        } 
        // 
        //打开303重定向网址 
        // 
        function JumpOpenUrl($url) 
        { 
                //重设各参数 
                $this->m_url = ""; 
                $this->m_urlpath = ""; 
                $this->m_scheme = "http"; 
                $this->m_host = ""; 
                $this->m_port = "80"; 
                $this->m_user = ""; 
                $this->m_pass = ""; 
                $this->m_path = "/"; 
                $this->m_query = ""; 
                $this->m_error = ""; 
                $this->JumpCount++; 
                $this->m_httphead = Array() ; 
                $this->m_html = ""; 
                $this->Close(); 
                //初始化系统 
                $this->PrivateInit($url); 
                $this->PrivateStartSession(); 
        } 
        // 
        //获得某操作错误的原因 
        // 
        function printError() 
        { 
                echo "错误信息：".$this->m_error; 
                echo "具体返回头：
"; 
                foreach($this->m_httphead as $k=>$v) 
                { echo "$k => $v 
\r\n"; } 
        } 
        // 
        //判别用Get方法发送的头的应答结果是否正确 
        // 
        function IsGetOK() 
        { 
                if( ereg("^2",$this->GetHead("http-state")) ) 
                {        return true; } 
                else 
                { 
                        $this->m_error .= $this->GetHead("http-state")." - ".$this->GetHead("http-describe")."
"; 
                        return false; 
                } 
        } 
        // 
        //看看返回的网页是否是text类型 
        // 
        function IsText() 
        { 
                if(ereg("^2",$this->GetHead("http-state")) 
                        && eregi("^text",$this->GetHead("content-type"))) 
                {        return true; } 
                else 
                { 
                        $this->m_error .= "内容为非文本类型或网址重定向
"; 
                        return false; 
                } 
        } 
        // 
        //判断返回的网页是否是特定的类型 
        // 
        function IsContentType($ctype) 
        { 
                if(ereg("^2",$this->GetHead("http-state")) 
                        && $this->GetHead("content-type")==strtolower($ctype)) 
                {        return true; } 
                else 
                { 
                        $this->m_error .= "类型不对 ".$this->GetHead("content-type")."
"; 
                        return false; 
                } 
        } 
        // 
        //用Http协议下载文件 
        // 
        function SaveToBin($savefilename) 
        { 
                if(!$this->IsGetOK()) return false; 
                if(@feof($this->m_fp)) { $this->m_error = "连接已经关闭！"; return false; } 
                $fp = fopen($savefilename,"w"); 
                while(!feof($this->m_fp)){ 
                        fwrite($fp,fread($this->m_fp,1024)); 
                } 
                fclose($this->m_fp); 

                fclose($fp); 
                return true; 
        } 
        // 
        //保存网页内容为Text文件 
        // 
        function SaveToText($savefilename) 
        { 
                if($this->IsText()) $this->SaveBinFile($savefilename); 
                else return ""; 
        } 
        // 
        //用Http协议获得一个网页的内容 
        // 
        function GetHtml() 
        { 
                if(!$this->IsText()) return ""; 
                if($this->m_html!="") return $this->m_html; 
                if(!$this->m_fp||@feof($this->m_fp)) return ""; 
                while(!feof($this->m_fp)){ 
                        $this->m_html .= fgets($this->m_fp,256); 
                } 
                @fclose($this->m_fp); 
                return $this->m_html; 
        } 
        // 
        //开始HTTP会话 
        // 
        function PrivateStartSession() 
        { 

                if(!$this->PrivateOpenHost()){ 
                        $this->m_error .= "打开远程主机出错!"; 
                        return false; 
                } 

                if($this->GetHead("http-edition")=="HTTP/1.1") $httpv = "HTTP/1.1"; 
                else $httpv = "HTTP/1.0"; 

                //发送固定的起始请求头GET、Host信息 
                fputs($this->m_fp,"GET ".$this->m_urlpath." $httpv\r\n"); 
                $this->m_puthead["Host"] = $this->m_host; 

                //发送用户自定义的请求头 
                if(!isset($this->m_puthead["Accept"])) { $this->m_puthead["Accept"] = "*/*"; } 
                if(!isset($this->m_puthead["User-Agent"])) { $this->m_puthead["User-Agent"] = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2)"; } 
                if(!isset($this->m_puthead["Refer"])) { $this->m_puthead["Refer"] = "http://".$this->m_puthead["Host"]; } 
                foreach($this->m_puthead as $k=>$v){ 
                        $k = trim($k); 
                        $v = trim($v); 
                        if($k!=""&&$v!=""){ 
                                fputs($this->m_fp,"$k: $v\r\n"); 
                        } 
                } 

                //发送固定的结束请求头 
                //HTTP1.1协议必须指定文档结束后关闭链接,否则读取文档时无法使用feof判断结束 
                if($httpv=="HTTP/1.1") fputs($this->m_fp,"Connection: Close\r\n\r\n"); 
                else fputs($this->m_fp,"\r\n"); 

                //获取应答头状态信息 
                $httpstas = explode(" ",fgets($this->m_fp,256)); 
                $this->m_httphead["http-edition"] = trim($httpstas[0]); 
                $this->m_httphead["http-state"] = trim($httpstas[1]); 
                $this->m_httphead["http-describe"] = ""; 
                for($i=2;$i                        $this->m_httphead["http-describe"] .= " ".trim($httpstas[$i]); 
                } 
                //获取详细应答头 
                while(!feof($this->m_fp)){ 
                        $line = trim(fgets($this->m_fp,256)); 
                        if($line == "") break; 
                        $hkey = ""; 
                        $hvalue = ""; 
                        $v = 0; 
                        for($i=0;$i                                if($v==1) $hvalue .= $line[$i]; 
                                if($line[$i]==":") $v = 1; 
                                if($v==0) $hkey .= $line[$i]; 
                        } 
                        $hkey = trim($hkey); 
                        if($hkey!="") $this->m_httphead[strtolower($hkey)] = trim($hvalue); 
                } 
                //判断是否是3xx开头的应答 
                if(ereg("^3",$this->m_httphead["http-state"])) 
                { 
                        if($this->JumpCount > 3) return; 
                        if(isset($this->m_httphead["location"])){ 
                                $newurl = $this->m_httphead["location"]; 
                                if(eregi("^http",$newurl)){ 
                                        $this->JumpOpenUrl($newurl); 
                                } 
                                else{ 
                                        $newurl = $this->FillUrl($newurl); 
                                        $this->JumpOpenUrl($newurl); 
                                } 
                        } 
                        else 
                        {        $this->m_error = "无法识别的转移应答！"; } 
                }// 
        } 
        // 
        //获得一个Http头的值 
        // 
        function GetHead($headname) 
        { 
                $headname = strtolower($headname); 
                if(isset($this->m_httphead[$headname])) 
                        return $this->m_httphead[$headname]; 
                else 
                        return ""; 
        } 
        // 
        //设置Http头的值 
        // 
        function SetHead($skey,$svalue) 
        { 
                $this->m_puthead[$skey] = $svalue; 
        } 
        // 
        //打开连接 
        // 
        function PrivateOpenHost() 
        { 
                if($this->m_host=="") return false; 
                $this->m_fp = @fsockopen($this->m_host, $this->m_port, &$errno, &$errstr,10); 
                if(!$this->m_fp){ 
                        $this->m_error = $errstr; 
                        return false; 
                } 
                else{ 
                        return true; 
                } 
        } 
        // 
        //关闭连接 
        // 
        function Close(){ 
                @fclose($this->m_fp); 
        } 
        // 
        //补全相对网址 
        // 
        function FillUrl($surl) 
  { 
    $i = 0; 
    $dstr = ""; 
    $pstr = ""; 
    $okurl = ""; 
    $pathStep = 0; 
    $surl = trim($surl); 
    if($surl=="") return ""; 
    $pos = strpos($surl,"#"); 
    if($pos>0) $surl = substr($surl,0,$pos); 
    if($surl[0]=="/"){ 
            $okurl = "http://".$this->HomeUrl."/".$surl; 
    } 
    else if($surl[0]==".") 
    { 
      if(strlen($surl)<=2) return ""; 
      else if($surl[0]=="/") 
      { 
              $okurl = "http://".$this->BaseUrlPath."/".substr($surl,2,strlen($surl)-2); 
            } 
      else{ 
        $urls = explode("/",$surl); 
        foreach($urls as $u){ 
          if($u=="..") $pathStep++; 
          else if($i          else $dstr .= $urls[$i]; 
          $i++; 
        } 
        $urls = explode("/",$this->BaseUrlPath); 
        if(count($urls) <= $pathStep) 
                return ""; 
        else{ 
          $pstr = "http://"; 
          for($i=0;$i          { $pstr .= $urls[$i]."/"; } 
          $okurl = $pstr.$dstr; 
        } 
      } 
    } 
    else 
    { 
      if(strlen($surl)<7) 
        $okurl = "http://".$this->BaseUrlPath."/".$surl; 
      else if(strtolower(substr($surl,0,7))=="http://") 
        $okurl = $surl; 
      else 
        $okurl = "http://".$this->BaseUrlPath."/".$surl; 
    } 
    $okurl = eregi_replace("^(http://)","",$okurl); 
    $okurl = eregi_replace("/{1,}","/",$okurl); 
    return "http://".$okurl; 
  } 
} 
?>