{"id":162,"date":"2017-10-12T18:56:00","date_gmt":"2017-10-12T18:56:00","guid":{"rendered":"https:\/\/www.mainmind.com\/blog\/?p=162"},"modified":"2020-07-27T07:21:13","modified_gmt":"2020-07-27T07:21:13","slug":"sintaxis-en-servicios-wcf-asincronos","status":"publish","type":"post","link":"https:\/\/www.mainmind.com\/blog\/sintaxis-en-servicios-wcf-asincronos\/","title":{"rendered":"Sintaxis en servicios WCF as\u00edncronos"},"content":{"rendered":"<p>A la hora de generar servicios escalables que aprovechen el procesamiento en paralelo algunos detalles sint&aacute;cticos deben realizarse literalmente. La nomenclatura puede perderse por el camino generando errores en el momento de ejecutar los servicios:<\/p>\n<pre class=\"brush:plain;auto-links:false;toolbar:false\" contenteditable=\"false\">Your begin method must take an AsyncCallback and an object as the last two arguments and return an IAsyncResult.\n\nSignatura no v&aacute;lida del m&eacute;todo Begin asincr&oacute;nico para el m&eacute;todo miFuncionAsyncIniciar en el tipo de XXXX. El m&eacute;todo Begin debe tomar AsyncCallback y un objeto como los dos &uacute;ltimos argumentos y devolver IAsyncResult<\/pre>\n<p>&nbsp;<\/p>\n<p><img decoding=\"async\" src=\"\/blog\/wp-content\/uploads\/\/2017\/WCF_begin.jpg\" alt=\"\" \/><\/p>\n<p>El procedimiento debe tener asociadas la tareas iniciando con el nombre Begin con los dos &uacute;ltimos par&aacute;metros AsynCallBack y object:<\/p>\n<p>&nbsp;<\/p>\n<pre class=\"brush:csharp;auto-links:false;toolbar:false\" contenteditable=\"false\">public interface IEjemplo\n{\n\n    [OperationContractAttribute]\n    string MiFuncion(string mensaje, int otroParametro);\n\n    [OperationContractAttribute(AsyncPattern = true)]\n    IAsyncResult BeginMiFuncion(string mensaje, int otroParametro, AsyncCallback callback, object asyncState);\n\n    \/\/No se especifica OperationContractAttribute para el m&eacute;todo de finalizaci&oacute;n.\n    string EndMiFuncion(IAsyncResult result);\n\n}\n<\/pre>\n<p>La documentaci&oacute;n esta clara pero la traducci&oacute;n puede generar confusi&oacute;n con un sencillo erros de sintaxis obligatoria.&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p><a href=\"https:\/\/docs.microsoft.com\/en-us\/dotnet\/framework\/wcf\/how-to-implement-an-asynchronous-service-operation\" target=\"_blank\" rel=\"noopener noreferrer\">How to: Implement an Asynchronous Service Operation<\/a><\/p>\n<p><a href=\"https:\/\/docs.microsoft.com\/en-us\/dotnet\/framework\/wcf\/feature-details\/sessions-instancing-and-concurrency\" target=\"_blank\" rel=\"noopener noreferrer\">Sessions, Instancing, and Concurrency<\/a><\/p>\n<p>&nbsp;<\/p>\n<p>Ejemplo completo de una excepci&oacute;n tipo:<\/p>\n<p>&nbsp;<\/p>\n<pre class=\"brush:csharp;auto-links:false;toolbar:false\" contenteditable=\"false\">System.InvalidOperationException: Signatura no v&aacute;lida del m&eacute;todo Begin asincr&oacute;nico para el m&eacute;todo UnirAsyncIniciar en el tipo de ServiceContract XXXXXX. El m&eacute;todo Begin debe tomar AsyncCallback y un objeto como los dos &uacute;ltimos argumentos y devolver IAsyncResult.\n   en System.ServiceModel.Description.ServiceReflector.IsBegin(OperationContractAttribute opSettings, MethodInfo method)\n   en System.ServiceModel.Description.TypeLoader.CreateOperationDescription(ContractDescription contractDescription, MethodInfo methodInfo, MessageDirection direction, ContractReflectionInfo reflectionInfo, ContractDescription declaringContract)\n   en System.ServiceModel.Description.TypeLoader.CreateOperationDescriptions(ContractDescription contractDescription, ContractReflectionInfo reflectionInfo, Type contractToGetMethodsFrom, ContractDescription declaringContract, MessageDirection direction)\n   en System.ServiceModel.Description.TypeLoader.CreateContractDescription(ServiceContractAttribute contractAttr, Type contractType, Type serviceType, ContractReflectionInfo&amp; reflectionInfo, Object serviceImplementation)\n   en System.ServiceModel.Description.TypeLoader.LoadContractDescriptionHelper(Type contractType, Type serviceType, Object serviceImplementation)\n   en System.ServiceModel.Description.ContractDescription.GetContract(Type contractType, Type serviceType)\n   en System.ServiceModel.ServiceHost.CreateDescription(IDictionary`2&amp; implementedContracts)\n   en System.ServiceModel.ServiceHostBase.InitializeDescription(UriSchemeKeyedCollection baseAddresses)\n   en System.ServiceModel.ServiceHost..ctor(Type serviceType, Uri[] baseAddresses)\n   en Microsoft.Tools.SvcHost.ServiceHostHelper.CreateServiceHost(Type type, ServiceKind kind)\n   en Microsoft.Tools.SvcHost.ServiceHostHelper.OpenService(ServiceInfo info)\n\n<\/pre>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>A la hora de generar servicios escalables que aprovechen el procesamiento en paralelo algunos detalles sint&aacute;cticos deben realizarse literalmente. La nomenclatura puede perderse por el camino generando errores en el momento de ejecutar los servicios: Your begin method must take an AsyncCallback and an object as the last two arguments and return an IAsyncResult. Signatura [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[15],"tags":[368,367,366,365,343],"class_list":["post-162","post","type-post","status-publish","format-standard","hentry","category-visual-studio","tag-asincrono","tag-async","tag-sintaxis","tag-syntax","tag-wcf"],"_links":{"self":[{"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/posts\/162","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/comments?post=162"}],"version-history":[{"count":0,"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/posts\/162\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/media?parent=162"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/categories?post=162"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.mainmind.com\/blog\/wp-json\/wp\/v2\/tags?post=162"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}