GetFileSizeEx的用法(比GetFileSize简单)

 1 void CGetFileSizeDlg::OnBnClickedButton1()
 2 {
 3     CString strFile;
 4     GetDlgItemText(IDC_EDIT1, strFile);
 5     DWORD dwHigh = 0;//(文件大小超过4GB)存放33-64位高位
 6     DWORD dwSize = 0;//存放1-32位地位
 7     HANDLE hFile = CreateFile(strFile, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
 8     if (hFile == INVALID_HANDLE_VALUE) {
 9         DWORD errCode = GetLastError();
10         CString szErr;
11         szErr.Format(_T("CreateFile出错啦!错误代码是%d"), errCode);
12         MessageBox(szErr);
13         CloseHandle(hFile);
14         return;
15     }
16     LARGE_INTEGER totalSize;//这里使用LARGE_INTEGER结构体
17     if (!GetFileSizeEx(hFile, &totalSize)) {
18         DWORD errCode = GetLastError();
19         CString szErr;
20         szErr.Format(_T("GetFileSizeEx出错啦!错误代码是%d"), errCode);
21         MessageBox(szErr);
22         CloseHandle(hFile);
23         return;
24     }
25     LONGLONG lTotal = totalSize.QuadPart;
26     DOUBLE dbTotal = (DOUBLE)lTotal;
27     DOUBLE kbSize = dbTotal / 1024;
28     DOUBLE mbSize = dbTotal / (1024*1024);
29     DOUBLE gbSize = dbTotal / (1024*1024*1024);
30     CString cbSize;
31     cbSize.Format(_T("文件大小是%lld字节(%0.2fKB,%0.2fMB,%0.2fGB)"), lTotal,kbSize,mbSize,gbSize);
32     MessageBox(cbSize);
33     CloseHandle(hFile);
34     return;
35 }