C++网页抓取

#include<windows.h>
#include<Wininet.h>
#include<iostream>
#include<fstream>
#include<string>
#pragma comment(lib,"WinInet.lib")


using namespace std;


int main()
{
HINTERNET hINet, hHttpFile;               
char szSizeBuffer[32];


DWORD dwLengthSizeBuffer = sizeof(szSizeBuffer);


hINet = InternetOpen("IE6.0", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0 );    //InternetOpen初始化WININET.DLL


string url = "http://www.sina.com";          //抓新浪网


if ( !hINet )
{
cout << "InternetOpen fail" << endl;
return 1;
}


hHttpFile = InternetOpenUrl(hINet, url.c_str(), NULL, 0, 0, 0);  //这个函数连接到一个网络服务器上并且最被从服务器上读取数据


if(!hHttpFile)
{
cout << "error open url" << endl;
return 1;
}


BOOL bQuery = HttpQueryInfo(hHttpFile,
HTTP_QUERY_CONTENT_LENGTH,
szSizeBuffer,
&dwLengthSizeBuffer, NULL); //得到关于文件的信息


if(bQuery ==false)
{
InternetCloseHandle(hINet); 
cout << "error query info" << endl;
return 3;


}


int FileSize=atol(szSizeBuffer);    //atol函数把字符串转换成长整型数
string revData;
revData.resize(FileSize);






DWORD dwBytesRead;
BOOL bRead = InternetReadFile(hHttpFile, &revData[0], FileSize, &dwBytesRead);     //web浏览器将在InternetReadFile上循环 ，不停地从Internet上读入数据块。






if(!bRead)
{
cout << "error to read file" << endl;
return 4;
}


ofstream   out_file("sina.html");   


out_file << revData;              //输出到文件


InternetCloseHandle(hHttpFile);   //关闭句柄


InternetCloseHandle(hINet);


cout << "抓取成功!/n" << endl;


system("pause");


return 0;
}