Calculate file size

How can we calculate text file size in bytes? Using VC++!

Code:

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int GetFileSize(const std::string& FileName)
{
  int Size;
  std::ifstream File;

  File.open(FileName.c_str(), std::ios::in | std::ios::binary);
  if(File.fail()) return -1;

  File.seekg(0, std::ios::end);
  Size = File.tellg();

  File.close();
  return Size;
}

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