// 功能：获取下载文件的大小
// 参数：url - 网络URL地址
// nFileSize - 输出文件的大小
// 返回值：返回true表示得到了文件的大小，URL地址有效; 返回false表示无法得到文件的信息
// 说明：这个接口是阻塞模式的，请不要在主线程调用
static public bool GetDownFileSize(string url, out int nOutFileSize, long nRandSeed = 0)
{
nOutFileSize = 0;
CHttp http = new CHttp(nRandSeed);
string szServerIP = string.Empty, szObj = string.Empty;
int nPort = 80;
http.ParseURL(url, ref szServerIP, ref szObj, ref nPort);
string szAnswer = string.Empty;
if (!http.QueryFile(ref szAnswer, szServerIP, nPort, szObj, 0, 1, false))
{
http.Close();
return(false);
}
int nDownSize = 0, nFileSize = 0;
if (!http.AnlyseFileLengthFromAnswer(szAnswer, ref nDownSize, ref nFileSize))
{
http.Close();
return(false);
}
http.Close();
nOutFileSize = nFileSize;
return(true);
}
// 功能：下载整个文件
// 说明：这个接口是阻塞模式的，请不要在主线程调用
static public bool DownFile(string url, out byte[] szFileData, int nDownOffset = 0, int nNeedDownSize = 0, long nRandSeed = 0, LPOnReceiveDownFile lpReceiveFunc = null)
{
szFileData = null;
CHttp http = new CHttp(nRandSeed);
string szServerIP = string.Empty, szObj = string.Empty;
int nPort = 80;
http.ParseURL(url, ref szServerIP, ref szObj, ref nPort);
string szAnswer = string.Empty;
if (!http.QueryFile(ref szAnswer, szServerIP, nPort, szObj, nDownOffset, nNeedDownSize, nNeedDownSize <= 0))
{
http.Close();
return(false);
}
int nDownSize = 0, nFileSize = 0;
if (!http.AnlyseFileLengthFromAnswer(szAnswer, ref nDownSize, ref nFileSize))
{
http.Close();
return(false);
}
nDownSize = nFileSize;
byte[] szTempBuf = null;
szFileData = new byte[nFileSize];
int nRecTotal = 0;
int nRecLen = 0;
int nOffset = 0;
while (nRecTotal < nDownSize)
{
nRecLen = http.FastReceiveMax(ref szTempBuf, ref nOffset);
// 写入文件吧
if (nRecLen > 0)
{
if (lpReceiveFunc != null)
{
lpReceiveFunc(nRecLen);
}
Array.Copy(szTempBuf, nOffset, szFileData, nRecTotal, nRecLen);
nRecTotal += nRecLen;
}
else
{
break;
}
}
http.Close();
return(nRecTotal == nDownSize);
}
static bool GetInetURL(string pcsURL, ref string szOutURL)
{
// 提取服务器的网址
string szURL = pcsURL;
if (szURL.IndexOf("http://", 0) != 0)
{
szURL = "http://" + szURL;
}
string szSerIP = GetMiddle(szURL, "http://", "/");
string szObj = string.Empty;
int nIndex = szURL.IndexOf('/', 6 + szSerIP.Length);
if (nIndex != -1)
{
szObj = szURL.Substring(nIndex); // 必须有'/'
}
else
{
return(false);
}
int nServerPort = 80;
nIndex = szSerIP.IndexOf(':', 0);
if (nIndex != -1)
{
nServerPort = DistillNumb(szSerIP, nIndex + 1);
szSerIP = szSerIP.Substring(0, nIndex);
}
// 连接服务器
CHttp tcpURL = new CHttp();
if (!tcpURL.ClientOpen(szSerIP, nServerPort))
{
return(false); // 无法连接服务器
}
// 格式化消息头
StringBuilder szBuilder = new StringBuilder(512);
///第1行:方法,请求的路径,版本
szBuilder.AppendFormat("GET {0} HTTP/1.1\r\n", szObj);
///第2行:主机
szBuilder.AppendFormat("Host:{0}\r\n", szSerIP);
///第3行: 引用网址
//szMsg.AppendFormat( "Referer:%s\r\n", szObj );
///第4行:接收的数据类型
szBuilder.Append("Accept:*/*\r\n");
///第5行:浏览器类型
szBuilder.Append("User-Agent:Mozilla/6.0 (compatible; MSIE 6.00; Android)\r\n");
///第6行:连接设置,保持
//szMsg.AppendFormat( "Connection:Keep-Alive\r\n" );
szBuilder.Append("Connection:close\r\n");
szBuilder.Append("Range: bytes=0-0\r\n");
szBuilder.Append("\r\n");
string szMsg = szBuilder.ToString();
tcpURL.SendToServer(szMsg);
byte [] chBuf = new byte[1];
char [] szTotalRecBuf = new char[1024]; // 应该不会这么长吧
int nTotalRecLen = 0;
int nStart = 0;
while (true)
{
int nRecLen = tcpURL.ReceiveChar(chBuf, 1024);
if (nRecLen <= 0)
{
break;
}
if (nTotalRecLen + nRecLen > szTotalRecBuf.Length)
{
char [] szNewBuf = new char[nTotalRecLen * 2];
Array.Copy(szTotalRecBuf, 0, szNewBuf, 0, nTotalRecLen);
szTotalRecBuf = szNewBuf;
}
szTotalRecBuf[nTotalRecLen++] = (char)chBuf[0];
nTotalRecLen += 1;
if (FindHttpMsgEndFlags(szTotalRecBuf, nTotalRecLen, ref nStart))
{
break;
}
}
tcpURL.Close();
szTotalRecBuf[nTotalRecLen] = '\0';
string szAnswer = new string(szTotalRecBuf, 0, nTotalRecLen);
// 分析
szOutURL = GetMiddle(szAnswer, "Location:", "\r\n");
szOutURL = szOutURL.Trim();
tcpURL.Close();
return(szOutURL.Length > 0);
}
// 功能：下载文件，并将下载的文件保存到本地
// 参数：url - 网络URL的地址
// szLocalPathName - 本地保存地址
// 说明：这个接口是阻塞模式的，请不要在主线程调用
static public bool DownFile(string url, string szLocalPathName, int nNeedDownOffset, int nNeedDownSize, long nRandSeed = 0, LPOnReceiveDownFile lpReceiveFunc = null)
{
CHttp http = new CHttp(nRandSeed);
string szServerIP = string.Empty, szObj = string.Empty;
int nPort = 80;
http.ParseURL(url, ref szServerIP, ref szObj, ref nPort);
string szAnswer = string.Empty;
if (!http.QueryFile(ref szAnswer, szServerIP, nPort, szObj, nNeedDownOffset, nNeedDownSize, nNeedDownSize <= 0))
{
http.Close();
return(false);
}
int nDownSize = 0, nFileSize = 0;
if (!http.AnlyseFileLengthFromAnswer(szAnswer, ref nDownSize, ref nFileSize))
{
http.Close();
return(false);
}
if (nNeedDownSize <= 0)
{
nDownSize = nFileSize; // 这是全部下载
}
// 打开本地文件
if (File.Exists(szLocalPathName))
{
File.Delete(szLocalPathName);
}
FileStream pFile = new FileStream(szLocalPathName, FileMode.CreateNew, FileAccess.Write);
// 开始下载吧
byte[] szTempBuf = null;
int nRecTotal = 0;
int nRecLen = 0;
int nOffset = 0;
while (nRecTotal < nDownSize)
{
nRecLen = http.FastReceiveMax(ref szTempBuf, ref nOffset);
// 写入文件吧
if (nRecLen > 0)
{
if (lpReceiveFunc != null)
{
lpReceiveFunc(nRecLen);
}
nRecTotal += nRecLen;
pFile.Write(szTempBuf, nOffset, nRecLen);
}
else
{
break;
}
}
http.Close();
pFile.Close();
return(nRecTotal == nDownSize);
}
