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Enumerating Files in a Job

To enumerate files in a job, call the IBackgroundCopyJob::EnumFiles method. The method returns an IEnumBackgroundCopyFiles interface pointer that you use to enumerate the files.

Note that the enumerated list is a snapshot of the files in the job at the time you call the EnumFiles method. However, the property values of those file objects reflect the current values of the file.

The following example shows how to enumerate files in a job and retrieve their properties. The example assumes the IBackgroundCopyJob interface pointer is valid.

HRESULT hr = 0;
IBackgroundCopyJob* pJob;
IEnumBackgroundCopyFiles* pFiles = NULL;
IBackgroundCopyFile* pFile = NULL;
IBackgroundCopyFile3* pFile3 = NULL;
WCHAR* pLocalFileName = NULL;
ULONG cFileCount = 0;
ULONG idx = 0;

hr = pJob->EnumFiles(&pFiles);
if (SUCCEEDED(hr))
{
  //Get the count of files in the job. 
  pFiles->GetCount(&cFileCount);

  //Enumerate the files in the job.
  for (idx=0; idx<cFileCount; idx++)
  {
    hr = pFiles->Next(1, &pFile, NULL);
    if (S_OK == hr)
    {
      // Query for the latest file interface.
      hr = pFile->QueryInterface(__uuidof(IBackgroundCopyFile3), (void**)&pFile3);
      pFile->Release();
      if (FAILED(hr))
      {
        wprintf(L"pFile->QueryInterface failed with 0x%x.\n", hr);
        goto cleanup;
      }

      // You can use the interface to retrieve the local and remote file
      // names, get the ranges to download if only part of the file content
      // is requested, determine the progress of the transfer, change the remote file
      // name, get the name of the temporary file that BITS uses to download
      // the file, determine if the file is downloaded from a peer, and set
      // the validation state of the file so it can be shared with peers.

      //Get the local name of the file.
      hr = pFile3->GetLocalName(&pLocalFileName);
      if (SUCCEEDED(hr))
      {
        //Do something with the file information.
      }

      CoTaskMemFree(pLocalFileName); 
      pFile3->Release();
      pFile3 = NULL;
    }
    else
    {
      //Handle error
      break;
    }
  }

  pFiles->Release();
  pFiles = NULL;
}