C# Google Drive:检索访问和刷新令牌时出错

我正在尝试从我的WP7应用程序访问google drive。但当我试图获取访问令牌以交换授权代码时，我从服务器收到了错误的请求

我在Fidler中看到的帖子请求：

POST https://accounts.google.com/o/oauth2/token HTTP/1.1
Accept: */*
Referer: file:///Applications/Install/7128457C-3AF4-41C4-A606-742068B1463F/Install/
Content-Length: 240
Accept-Encoding: identity
Content-Type: application/x-www-form-urlencoded
User-Agent: NativeHost
Host: accounts.google.com
Connection: Keep-Alive
Cache-Control: no-cache

code=<*Authorization_Code*>&
client_id=<*My_Client_Id*>&
client_secret=<*My_Client_Secret*>&
redirect_uri=urn%3aietf%3awg%3aoauth%3a2.0%3aoob&
grant_type=authorization_code

我的代码：

StringBuilder postData = new StringBuilder();
postData.AppendFormat("{0}={1}", "code",        HttpUtility.UrlEncode(AuthorizationCode));
postData.AppendFormat("&\n{0}={1}", "client_id", HttpUtility.UrlEncode(ClientId));
postData.AppendFormat("&\n{0}={1}", "client_secret", HttpUtility.UrlEncode(ClientSecret));
postData.AppendFormat("&\n{0}={1}", "redirect_uri", HttpUtility.UrlEncode("urn:ietf:wg:oauth:2.0:oob"));
postData.AppendFormat("&\n{0}={1}", "grant_type", HttpUtility.UrlEncode("authorization_code"));

WebClient client = new WebClient();
client.UploadStringCompleted += TokenResponse;
client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";

client.UploadStringAsync(new Uri("https://accounts.google.com/o/oauth2/token",UriKind.Absolute), "POST", postData.ToString());

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我在emulator和Lumia 820上都得到了这个结果。我也尝试在POST请求中不使用HttpUtility，但没有成功。有什么帮助吗？

可能是因为您正在通过

\n

在所有参数/值对之间添加新行

我不用它，不用它，它就能工作-

StringBuilder postData = new StringBuilder();
postData.AppendFormat("{0}={1}", "code",        HttpUtility.UrlEncode(AuthorizationCode));
postData.AppendFormat("&\n{0}={1}", "client_id", HttpUtility.UrlEncode(ClientId));
postData.AppendFormat("&\n{0}={1}", "client_secret", HttpUtility.UrlEncode(ClientSecret));
postData.AppendFormat("&\n{0}={1}", "redirect_uri", HttpUtility.UrlEncode("urn:ietf:wg:oauth:2.0:oob"));
postData.AppendFormat("&\n{0}={1}", "grant_type", HttpUtility.UrlEncode("authorization_code"));

WebClient client = new WebClient();
client.UploadStringCompleted += TokenResponse;
client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";

client.UploadStringAsync(new Uri("https://accounts.google.com/o/oauth2/token",UriKind.Absolute), "POST", postData.ToString());