如何使用createfile创建的文件句柄部分修改文件内容

Question

如题，
比如源文本文件内容为12345
我想把它改为12245
该如何操作
若创建方式改为createalways，则会直接清空源文件
还是说只能创建一个副本文件，读取时向副本写入

Answer 1

修改成功

#include "windows.h"

int _tmain(int argc, _TCHAR* argv[])
{
    HANDLE hFile = CreateFileA("C:\\1.txt", GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_ALWAYS, 0, NULL);
    DWORD dwOnceWrote;
    LARGE_INTEGER liCurrentPosition;
    liCurrentPosition.LowPart=2;
    liCurrentPosition.HighPart=0;
    SetFilePointerEx(hFile,liCurrentPosition,&liCurrentPosition,FILE_BEGIN);
    WriteFile(hFile,"2",1,&dwOnceWrote,NULL);
    CloseHandle(hFile);
    return 0;
}