发布一个用PHP fsockopen写的HTTP下载的类

　　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：



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=newDedeHttpDown();
$hd->OpenUrl(
echo$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
//作者:IT柏拉图
//时间:2005-11-1312:39
//声明:首发在落伍者网站，转载请保留版权信息
---------------------------------------------------------------------*/
classDedeHttpDown
{
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$JumpCount=0;//防止多重重定向陷入死循环
//
//初始化系统
//
functionPrivateInit($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);
$this->BaseUrlPath=ereg_replace(/$,,$this->BaseUrlPath);
}
}
//
//打开指定网址
//
functionOpenUrl($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);
$this->PrivateStartSession();
}
//
//打开303重定向网址
//
functionJumpOpenUrl($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);
$this->PrivateStartSession();
}
//
//获得某操作错误的原因
//
functionprintError()
{
echo错误信息：.$this->m_error;
echo具体返回头：<br>;
foreach($this->m_httpheadas$k=>$v)
{echo$k=>$v<br>\r\n;}
}
//
//判别用Get方法发送的头的应答结果是否正确
//
functionIsGetOK()
{
if(ereg(^2,$this->GetHead(http-state)))
{returntrue;}
else
{
$this->m_error.=$this->GetHead(http-state).-.$this->GetHead(http-describe).<br>;
returnfalse;
}
}
//
//看看返回的网页是否是text类型
//
functionIsText()
{
if(ereg(^2,$this->GetHead(http-state))
&&eregi(^text,$this->GetHead(content-type)))
{returntrue;}
else
{
$this->m_error.=内容为非文本类型或网址重定向<br>;
returnfalse;
}
}
//
//判断返回的网页是否是特定的类型
//
functionIsContentType($ctype)
{
if(ereg(^2,$this->GetHead(http-state))
&&$this->GetHead(content-type)==strtolower($ctype))
{returntrue;}
else
{
$this->m_error.=类型不对.$this->GetHead(content-type).<br>;
returnfalse;
}
}
//
//用Http协议下载文件
//
functionSaveToBin($savefilename)
{
if(!$this->IsGetOK())returnfalse;
if(@feof($this->m_fp)){$this->m_error=连接已经关闭！;returnfalse;}
$fp=fopen($savefilename,w);
while(!feof($this->m_fp)){
fwrite($fp,fread($this->m_fp,1024));
}
fclose($this->m_fp);

fclose($fp);
returntrue;
}
//
//保存网页内容为Text文件
//
functionSaveToText($savefilename)
{
if($this->IsText())$this->SaveBinFile($savefilename);
elsereturn;
}
//
//用Http协议获得一个网页的内容
//
functionGetHtml()
{
if(!$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
//
functionPrivateStartSession()
{

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

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;MSIE6.0;WindowsNT5.2);}
if(!isset($this->m_puthead[Refer])){$this->m_puthead[Refer]=
foreach($this->m_putheadas$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);
elsefputs($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;$i<count($httpstas);$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;$i<strlen($line);$i++){
if($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
{$this->m_error=无法识别的转移应答！;}
}//
}
//
//获得一个Http头的值
//
functionGetHead($headname)
{
$headname=strtolower($headname);
if(isset($this->m_httphead[$headname]))
return$this->m_httphead[$headname];
else
return;
}
//
//设置Http头的值
//
functionSetHead($skey,$svalue)
{
$this->m_puthead[$skey]=$svalue;
}
//
//打开连接
//
functionPrivateOpenHost()
{
if($this->m_host==)returnfalse;
$this->m_fp=@fsockopen($this->m_host,$this->m_port,&$errno,&$errstr,10);
if(!$this->m_fp){
$this->m_error=$errstr;
returnfalse;
}
else{
returntrue;
}
}
//
//关闭连接
//
functionClose(){
@fclose($this->m_fp);
}
//
//补全相对网址
//
functionFillUrl($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]==/){
$okurl=
}
elseif($surl[0]==.)
{
if(strlen($surl)<=2)return;
elseif($surl[0]==/)
{
$okurl=
}
else{
$urls=explode(/,$surl);
foreach($urlsas$u){
if($u==..)$pathStep++;
elseif($i<count($urls)-1)$dstr.=$urls[$i]./;
else$dstr.=$urls[$i];
$i++;
}
$urls=explode(/,$this->BaseUrlPath);
if(count($urls)<=$pathStep)
return;
else{
$pstr=
for($i=0;$i<count($urls)-$pathStep;$i++)
{$pstr.=$urls[$i]./;}
$okurl=$pstr.$dstr;
}
}
}
else
{
if(strlen($surl)<7)
$okurl=
elseif(strtolower(substr($surl,0,7))==
$okurl=$surl;
else
$okurl=
}
$okurl=eregi_replace(^(
$okurl=eregi_replace(/{1,},/,$okurl);
return
}
}
?>