fstream ifstream ofstream分块读写文件

 fstream ifstream ofstream分块读写文件

#include <fstream>
#include <algorithm>
#include <iostream>
using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{
    const int BUFFER_SIZE = 1024 * 10;
    std::ifstream ifs("e://setup_10.2.0.2001s.exe", ios::binary);
    std::ofstream ofs("e://setup_10.2.0.2001s2.exe", ios::binary);
    if (ifs) {
        ifs.seekg(0, ifs.end);
        int length = (int)ifs.tellg();
        ifs.seekg(0, ifs.beg);
        std::string buffer(BUFFER_SIZE, '\0');
        int offset = 0;
        int readSize = min(BUFFER_SIZE, length - offset);
        while (readSize > 0 && ifs.read(&buffer[0], readSize)) {
            ofs.write(&buffer[0], readSize);
            offset += readSize;
            readSize = min(BUFFER_SIZE, length - offset);
            std::cout << "offset:" << offset << std::endl;
        }
    }
    ifs.close();
    ofs.close();

    system("pause");
    return 0;
}

 参考链接：fstream ifstream ofstream分块读写文件