VB.NET UWP/WinRT Google Drive: Download a File (Stream to the Filesystem)

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Downloads the content of a file by ID. (In this example the file id = 1R_70heIyzIAu1_u0prXbYcaIiJRVkgBl) The file is streamed directly to the filesystem. Note: The alt=media query param must be used to download the file content (as opposed to the file metadata).

Documentation: https://developers.google.com/drive/v3/reference/files/get

Dim rest As New Chilkat.Rest
Dim success As Boolean

'   Provide a previously obtained OAuth2 access token.
Dim oauth2 As New Chilkat.OAuth2
oauth2.AccessToken = "OAUTH2_ACCESS_TOKEN"
rest.SetAuthOAuth2(oauth2)

success = Await rest.ConnectAsync("www.googleapis.com",443,True,True)
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


rest.AddQueryParam("includeTeamDriveItems","true")
rest.AddQueryParam("supportsTeamDrives","true")
rest.AddQueryParam("alt","media")

'  First send the HTTP request.
success = Await rest.SendReqNoBodyAsync("GET","/drive/v3/files/1R_70heIyzIAu1_u0prXbYcaIiJRVkgBl")
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


'  Read the response header.  If the response status code is success, stream to the file.
'  Otherwise receive the error response text.
Dim statusCode As Integer = Await rest.ReadResponseHeaderAsync()
If (statusCode < 0) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If

If (statusCode <> 200) Then
    Debug.WriteLine("Received error response code: " & statusCode)
    '  Read the error response body.
    Dim sbErrResponse As New Chilkat.StringBuilder
    success = Await rest.ReadRespSbAsync(sbErrResponse)
    If (success <> True) Then
        Debug.WriteLine(rest.LastErrorText)
        Exit Sub
    End If

    Debug.WriteLine("Error response:" & sbErrResponse.GetAsString())
    Exit Sub
End If

'  Stream the response body to the output file.
Dim respBodyStream As New Chilkat.Stream
respBodyStream.SinkFile = "/someDirectory/penguins.jpg"
success = Await rest.ReadRespBodyStreamAsync(respBodyStream,True)
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If



Debug.WriteLine("Example Completed.")