从vb.net网页调用Twitter Streaming API（状态/过滤器）

Question

我正在尝试在.net网页中调用Streaming API过滤器。

我确实在Twitter上创建了一个应用程序并获取了所需的凭据（消费者密钥，消费者密钥，访问令牌和访问令牌秘密）

这是使用

的代码

void scr2obj(double &ox,double &oy,double sx,double sy) 
 { 
 // ox=(sx-x0)/zoom; 
 // oy=(sy-y0)/zoom; 
 ox=(sx/zoom)-x0; 
 oy=(sy/zoom)-y0; 
 } 
//--------------------------------------------------------------------------- 
void obj2scr(double &sx,double &sy,double ox,double oy) 
 { 
 // sx=x0+(ox*zoom); 
 // sy=y0+(oy*zoom); 
 sx=(x0+ox)*zoom; 
 sy=(y0+oy)*zoom; 
 } 
//--------------------------------------------------------------------------- 
void __fastcall TForm1::FormMouseWheelDown(TObject *Sender, TShiftState Shift,TPoint &MousePos, bool &Handled) 
 { 
 double mx0,my0; 
 scr2obj(mx0,my0,mx,my); 
 zoom/=1.25; // zoom out 
 obj2scr(mx0,my0,mx0,my0); 
 // x0+=mx-mx0; 
 // y0+=my-my0; 
 x0+=(mx-mx0)/zoom; 
 y0+=(my-my0)/zoom; 
 _redraw=true; 
 } 
//--------------------------------------------------------------------------- 
void __fastcall TForm1::FormMouseWheelUp(TObject *Sender, TShiftState Shift, TPoint &MousePos, bool &Handled) 
 { 
 double mx0,my0; 
 scr2obj(mx0,my0,mx,my); 
 zoom*=1.25; // zoom in 
 obj2scr(mx0,my0,mx0,my0); 
 // x0+=mx-mx0; 
 // y0+=my-my0; 
 x0+=(mx-mx0)/zoom; 
 y0+=(my-my0)/zoom; 
 _redraw=true; 
 } 
//---------------------------------------------------------------------------

该功能不会返回任何内容。在调试模式下包含 Public Function StreamAPI() Dim url As String = "https://stream.twitter.com/1.1/statuses/filter.json?track=example.com/example" Dim oauthconsumerkey As String = "consumerkey" Dim oauthconsumersecret As String = "consumersecret" Dim oauthsignaturemethod As String = "HMAC-SHA1" Dim oauthversion As String = "1.0" Dim oauthtoken As String = "token" Dim oauthtokensecret As String = "tokenkey" Dim oauthnonce As String = Convert.ToBase64String(New ASCIIEncoding().GetBytes(DateTime.Now.Ticks.ToString())) Dim timeSpan As TimeSpan = DateTime.UtcNow - New DateTime(1970, 1, 1, 0, 0, 0, _ 0, DateTimeKind.Utc) Dim oauthtimestamp As String = Convert.ToInt64(timeSpan.TotalSeconds).ToString() Dim basestringParameters As New SortedDictionary(Of String, String)() basestringParameters.Add("track", "example.com/example") basestringParameters.Add("oauth_version", oauthversion) basestringParameters.Add("oauth_consumer_key", oauthconsumerkey) basestringParameters.Add("oauth_nonce", oauthnonce) basestringParameters.Add("oauth_signature_method", oauthsignaturemethod) basestringParameters.Add("oauth_timestamp", oauthtimestamp) basestringParameters.Add("oauth_token", oauthtoken) Dim baseString As New StringBuilder() baseString.Append("GET" + "&") baseString.Append(EncodeCharacters(Uri.EscapeDataString(url.Split("?"c)(0)) + "&")) For Each entry As KeyValuePair(Of String, String) In basestringParameters baseString.Append(EncodeCharacters(Uri.EscapeDataString(entry.Key + "=" + entry.Value + "&"))) Next Dim finalBaseString As String = baseString.ToString().Substring(0, baseString.Length - 3) Dim signingKey As String = EncodeCharacters(Uri.EscapeDataString(oauthconsumersecret)) + "&" + EncodeCharacters(Uri.EscapeDataString(oauthtokensecret)) 'Sign the request Dim hasher As New HMACSHA1(New ASCIIEncoding().GetBytes(signingKey)) Dim oauthsignature As String = Convert.ToBase64String(hasher.ComputeHash(New ASCIIEncoding().GetBytes(finalBaseString))) Dim webRequest__1 As HttpWebRequest = DirectCast(WebRequest.Create(url), HttpWebRequest) Dim authorizationHeaderParams As New StringBuilder() authorizationHeaderParams.Append("OAuth ") authorizationHeaderParams.Append("oauth_nonce=" + """" + Uri.EscapeDataString(oauthnonce) + """,") authorizationHeaderParams.Append("oauth_signature_method=" + """" + Uri.EscapeDataString(oauthsignaturemethod) + """,") authorizationHeaderParams.Append("oauth_timestamp=" + """" + Uri.EscapeDataString(oauthtimestamp) + """,") authorizationHeaderParams.Append("oauth_consumer_key=" + """" + Uri.EscapeDataString(oauthconsumerkey) + """,") If Not String.IsNullOrEmpty(oauthtoken) Then authorizationHeaderParams.Append("oauth_token=" + """" + Uri.EscapeDataString(oauthtoken) + """,") End If authorizationHeaderParams.Append("oauth_signature=" + """" + Uri.EscapeDataString(oauthsignature) + """,") authorizationHeaderParams.Append("oauth_version=" + """" + Uri.EscapeDataString(oauthversion) + """") webRequest__1.Headers.Add("Authorization", authorizationHeaderParams.ToString) webRequest__1.Method = "GET" webRequest__1.ContentType = "application/x-www-form-urlencoded" webRequest__1.Timeout = 3 * 60 * 1000 Try Dim webResponse As HttpWebResponse = TryCast(webRequest__1.GetResponse(), HttpWebResponse) Dim dataStream As System.IO.Stream = webResponse.GetResponseStream() ' Open the stream using a StreamReader for easy access. Dim reader As New StreamReader(dataStream) ' Read the content. Dim responseFromServer As String responseFromServer = reader.ReadToEnd() Return responseFromServer Catch ex As Exception End Try End Function 的行显示“无法计算表达式”。

如果网址采用此格式，则相同的代码可以正常工作 https://api.twitter.com/1.1/application/rate_limit_status.json 要么 https://api.twitter.com/1.1/search/tweets.json?q=example

为什么它不适用于流apis？我不能使用搜索API，因为它不会返回我需要的所有结果，例如搜索API不会返回包含网址的推文。

我按照Twitter网站的建议为.net项目尝试了tweetinvi库。

reader.ReadToEnd()

但这不会返回任何东西。事件没有被调用，我没有得到任何结果。

两种方法都失败了。还有其他明显的例子我可以用来从vb.net网页调用状态/过滤器吗？

Answer 1

我是Tweetinvi的开发者。

您的代码看起来是正确的。你能不能告诉我你收到的例外情况。

另外，我不确定是否直接在页面中调用此代码（我不熟悉WebForms），但请注意StartStreamMatchingAllConditions将阻止它运行的Thread直到溪流停止。

如果您想让它在场景后面运行，您需要使用async版本：StartStreamMatchingAllConditionsAsync()。

最后，我将流推文发送到UI的方式是使用WebSocket并将信息从服务器发送到javascript处理程序。