¿Cómo puedo configurar los encabezados con Silverlight GET HttpWebRequest?
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05-07-2019 - |
Pregunta
Realizar una solicitud a un servicio RESTful en Silverlight con HttpWebRequest funciona bien siempre y cuando no agregue ningún encabezado a la solicitud.
Tan pronto como añada un encabezado con un código como este
var webReq = (HttpWebRequest)WebRequest.Create(new Uri(_RemoteAddress, "GetProviderMetadata"));
webReq.Method = HttpMethodType.Get;
webReq.Headers["SomeToken"] = "someTokenValue";
Recibo la excepción pegada al final de esta pregunta tan pronto como se llama a EndGetResponse ()
. Alguien sabe por qué esto es? Añadir encabezados para obtener solicitudes parece funcionar bien en .NET normal, así que supongo que es una limitación de Silverlight, pero no puedo encontrar ninguna documentación que aclare.
{System.NotSupportedException ---> System.NotSupportedException: Specified method is not supported.
at System.Net.BrowserHttpWebRequest.InternalEndGetResponse(IAsyncResult asyncResult)
at System.Net.BrowserHttpWebRequest.<>c__DisplayClass5.<EndGetResponse>b__4(Object sendState)
at System.Net.AsyncHelper.<>c__DisplayClass2.<BeginOnUI>b__0(Object sendState)
--- End of inner exception stack trace ---
at System.Net.AsyncHelper.BeginOnUI(SendOrPostCallback beginMethod, Object state)
at System.Net.BrowserHttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at System.Net.BrowserHttpWebRequest.<>c__DisplayClassd.<InvokeGetResponseCallback>b__b(Object state2)
at System.Threading._ThreadPoolWaitCallback.WaitCallback_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallbackInternal(_ThreadPoolWaitCallback tpWaitCallBack)
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback(Object state)}
[System.NotSupportedException]: {System.NotSupportedException ---> System.NotSupportedException: Specified method is not supported.
at System.Net.BrowserHttpWebRequest.InternalEndGetResponse(IAsyncResult asyncResult)
at System.Net.BrowserHttpWebRequest.<>c__DisplayClass5.<EndGetResponse>b__4(Object sendState)
at System.Net.AsyncHelper.<>c__DisplayClass2.<BeginOnUI>b__0(Object sendState)
--- End of inner exception stack trace ---
at System.Net.AsyncHelper.BeginOnUI(SendOrPostCallback beginMethod, Object state)
at System.Net.BrowserHttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at System.Net.BrowserHttpWebRequest.<>c__DisplayClassd.<InvokeGetResponseCallback>b__b(Object state2)
at System.Threading._ThreadPoolWaitCallback.WaitCallback_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallbackInternal(_ThreadPoolWaitCallback tpWaitCallBack)
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback(Object state)}
_className: "System.NotSupportedException"
_data: {System.Collections.ListDictionaryInternal}
_dynamicMethods: null
_exceptionMethod: null
_exceptionMethodString: null
_helpURL: null
_HResult: -2146233067
_innerException: {System.NotSupportedException: Specified method is not supported.
at System.Net.BrowserHttpWebRequest.InternalEndGetResponse(IAsyncResult asyncResult)
at System.Net.BrowserHttpWebRequest.<>c__DisplayClass5.<EndGetResponse>b__4(Object sendState)
at System.Net.AsyncHelper.<>c__DisplayClass2.<BeginOnUI>b__0(Object sendState)}
_message: ""
_remoteStackIndex: 0
_remoteStackTraceString: null
_source: "System.Windows"
_stackTrace: {sbyte[192]}
_stackTraceString: null
_xcode: -532462766
_xptrs: 0
Data: {System.Collections.ListDictionaryInternal}
HelpLink: null
HResult: -2146233067
InnerException: {System.NotSupportedException: Specified method is not supported.
at System.Net.BrowserHttpWebRequest.InternalEndGetResponse(IAsyncResult asyncResult)
at System.Net.BrowserHttpWebRequest.<>c__DisplayClass5.<EndGetResponse>b__4(Object sendState)
at System.Net.AsyncHelper.<>c__DisplayClass2.<BeginOnUI>b__0(Object sendState)}
Message: ""
Source: "System.Windows"
StackTrace: " at System.Net.AsyncHelper.BeginOnUI(SendOrPostCallback beginMethod, Object state)\r\n at System.Net.BrowserHttpWebRequest.EndGetResponse(IAsyncResult asyncResult)\r\n at Intellidimension.RdfEntity.Service.RemoteEntityServiceProviderClient.getProviderMetadataResponse(IAsyncResult result)\r\n at System.Net.BrowserHttpWebRequest.<>c__DisplayClassd.<InvokeGetResponseCallback>b__b(Object state2)\r\n at System.Threading._ThreadPoolWaitCallback.WaitCallback_Context(Object state)\r\n at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)\r\n at System.Threading._ThreadPoolWaitCallback.PerformWaitCallbackInternal(_ThreadPoolWaitCallback tpWaitCallBack)\r\n at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback(Object state)"
System.Runtime.InteropServices._Exception.HelpLink: null
System.Runtime.InteropServices._Exception.Source: "System.Windows"
Solución
Silverlight solo admite la configuración de encabezados utilizando el método POST, no el método GET. Esto se debe a una limitación en la forma en que se implementa la pila TCP / IP en Silverlight. Utiliza las API de extensión del navegador en lugar de ir directamente contra las API del sistema operativo del host.
Otros consejos
Especifique " Cliente HTTP " manejo antes de que llame, inicie su Solicitud Web.
Me gusta esto:
bool httpResult = WebRequest.RegisterPrefix("http://", WebRequestCreator.ClientHttp);
bool httpsResult = WebRequest.RegisterPrefix("https://", WebRequestCreator.ClientHttp);