PHP 远程文件类(支持断点续传)

PHP 远程文件类(支持断点续传)

 <?php
/**
 * 下载远程文件类支持断点续传 
 */
class HttpDownload {
 private $m_url = "";
 private $m_urlpath = "";
 private $m_scheme = "http";
 private $m_host = "";
 private $m_port = "80";
 private $m_user = "";
 private $m_pass = "";
 private $m_path = "/";
 private $m_query = "";
 private $m_fp = "";
 private $m_error = "";
 private $m_httphead = "" ;
 private $m_html = "";
 
 /**
 * 初始化 
 */
 public function PrivateInit($url){
 $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;
 }
 }
 }
 
 /**
 * 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->m_httphead = "" ;
 $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
 */
 public function printError() {
 echo "错误信息：".$this->m_error;
 echo "具体返回头：<br>";
 foreach($this->m_httphead as $k=>$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
 */
 public function IsGetOK() {
 if( ereg("^2",$this->GetHead("http-state")) ) { 
 return true; 
 } else {
 $this->m_error .= $this->GetHead("http-state")." - ".$this->GetHead("http-describe")."<br>";
 return false;
 }
 }
 
 /**
 * 看看返回的网页是否是text类型
 */
 public function IsText() {
 if (ereg("^2",$this->GetHead("http-state")) && eregi("^text",$this->GetHead("content-type"))) { 
 return true; 
 } else {
 $this->m_error .= "内容为非文本类型<br>";
 return false;
 }
 }
 /**
 * 判断返回的网页是否是特定的类型
 */
 public function IsContentType($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")."<br>";
 return false;
 }
 }
 
 /**
 * 用 HTTP 协议下载文件
 */
 public 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") or die("写入文件 $savefilename 失败！");
 while (!feof($this->m_fp)) {
 @fwrite($fp,fgets($this->m_fp,256));
 }
 @fclose($this->m_fp);
 return true;
 }
 
 /**
 * 保存网页内容为 Text 文件
 */
 public function SaveToText($savefilename) {
 if ($this->IsText()) {
 $this->SaveBinFile($savefilename);
 } else {
 return "";
 }
 }
 
 /**
 * 用 HTTP 协议获得一个网页的内容
 */
 public 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
 */
 public 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 {
 $httpv = "HTTP/1.0";
 }
 fputs($this->m_fp,"GET ".$this->m_urlpath." $httpv\r\n");
 fputs($this->m_fp,"Host: ".$this->m_host."\r\n");
 fputs($this->m_fp,"Accept: */*\r\n");
 fputs($this->m_fp,"User-Agent: Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.2)\r\n");
 #HTTP1.1协议必须指定文档结束后关闭链接,否则读取文档时无法使用feof判断结束
 if ($httpv=="HTTP/1.1") {
 fputs($this->m_fp,"Connection: Close\r\n\r\n");
 } else {
 fputs($this->m_fp,"\r\n");
 }
 $httpstas = fgets($this->m_fp,256);
 $httpstas = split(" ",$httpstas);
 $this->m_httphead["http-edition"] = trim($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[$i]);
 }
 while (!feof($this->m_fp)) {
 $line = str_replace("\"","",trim(fgets($this->m_fp,256)));
 if($line == "") break;
 if (ereg(":",$line)) {
 $lines = split(":",$line);
 $this->m_httphead[strtolower(trim($lines[0]))] = trim($lines[1]);
 }
 }
 }
 
 /**
 * 获得一个Http头的值
 */
 public function GetHead($headname) {
 $headname = strtolower($headname);
 if (isset($this->m_httphead[$headname])) {
 return $this->m_httphead[$headname];
 } else {
 return "";
 }
 }
 
 /**
 * 打开连接
 */
 public 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
 */
 public function Close(){
 @fclose($this->m_fp);
 }
}

#两种使用方法，分别如下：

#打开网页
$httpdown = new HttpDownload();
$httpdown->OpenUrl("http://www.75271.com");
echo $httpdown->GetHtml();
$httpdown->Close();


#下载文件
$file = new HttpDownload(); # 实例化类
$file->OpenUrl("http://www.75271.com/cn/test.pdf"); # 远程文件地址
$file->SaveToBin("test.pdf"); # 保存路径及文件名
$file->Close(); # 释放资源
?>