public async Task DeleteFileAsync(string directoryName, string fileName)
{
Validate.String(directoryName, "directoryName");
Validate.String(fileName, "fileName");
var rootDirectory = cloudFileShare.GetRootDirectoryReference();
var directoryToUpdate = rootDirectory.GetDirectoryReference(directoryName);
var file = directoryToUpdate.GetFileReference(fileName);
await file.DeleteIfExistsAsync();
}
}