javascript - How to call a web method async in ASP.NET (SharePoint behind) -

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• is there way handle async/await behind asmx service? 2 answers

calling async web method, 500 error. there other ways call web method async?

stacktrace:

server error in '/' application.

unknown web method sendmessage. parameter name: methodname
description: unhandled exception occurred during execution of current web request. please review stack trace more information error , originated in code.

exception details: system.argumentexception: unknown web method sendmessage. parameter name: methodname

source error:

an unhandled exception generated during execution of current web request. information regarding origin , location of exception can identified using exception stack trace below.

stack trace:

[argumentexception: unknown web method sendmessage. parameter name: methodname]
system.web.handlers.scriptmodule.onpostacquirerequeststate(object sender, eventargs eventargs) +728343
system.web.synceventexecutionstep.system.web.httpapplication.iexecutionstep.execute() +92 system.web.httpapplication.executestep(iexecutionstep step, boolean& completedsynchronously) +165

version information: microsoft .net framework version:4.0.30319; asp.net version:4.0.30319.34248

aspx codebehind:

namespace any.contact {     using system.threading.tasks;     using system.web.services;      public partial class contactformpage : publishinglayoutpage     {             [webmethod]         public static async task<bool> sendmessage(string topic, string message)         {             return await sendemail(topic, message);         }     } } 

javascript:

$.ajax({    type: "get",    url: window.location.href + "/sendmessage",    data: {      "topic": jquery('.ddl-topic').val(),      "message": jquery('.tb-message').val()    },    contenttype: "application/json; charset=utf-8",    datatype: "json",    async: true,    cache: false,    success: function() {      $('.alert.alert-success').toggleclass('hidden', 'show');    },    error: function() {      $('.alert.alert-danger').toggleclass('hidden', 'show');    }  });

you don't need use task, it'll called asynchronous js. can regular method returns bool. try:

namespace any.contact {     using system.threading.tasks;     using system.web.services;      public partial class contactformpage : publishinglayoutpage     {             [webmethod]         public static bool sendmessage(string topic, string message)         {             return sendemail(topic, message);         }     } }