Purushotam Sahon Stack Overflow • Recommends
On “How to generate access token using refresh token through google drive API?”
Using Post call, worked for me.
RestClient restClient = new RestClient();
RestRequest request = new RestRequest();
request.AddQueryParameter("client_id", "value");
request.AddQueryParameter("client_secret", "value");
request.AddQueryParameter("grant_type", "refresh_token");
request.AddQueryParameter("refresh_token", "value");
restClient.BaseUrl = new System.Uri("https://oauth2.googleapis.com/token");
restClient.Post(request);
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