c# - How to await a byte[] -

i have mvc 4 app. 1 of things send email calling service using webclient so:

var serializer = new javascriptserializer(); string requestdata = serializer.serialize(new {     eventid = 1,     subscriberid = studentid,     tolist = loginmodel.emailaddress,     templateparamvals = strstudentdetails, });  using (var client = new webclient()) {     client.headers[httprequestheader.contenttype] = "application/json";     var result = await client.uploaddata(uri, encoding.utf8.getbytes(requestdata)); } 

i wanted make use of uploaddataasync got error:

an asynchronous operation cannot started @ time. asynchronous operations may started within asynchronous handler or module or during events in page lifecycle.

so thought of creating wrapper function & making asynchronous while still using uploaddataasync.

private async task<bool> sendemailasync(long studentid, loginmodel loginmodel) {     try     {         string uri = configurationmanager.appsettings["communicationmanagerurl"] + "postuserevent";         var serializer = new javascriptserializer();          string requestdata = serializer.serialize(new         {             eventid = 1,             subscriberid = studentid,             tolist = loginmodel.emailaddress,             templateparamvals = strstudentdetails,         });          using (var client = new webclient())         {             client.headers[httprequestheader.contenttype] = "application/json";             var result = await client.uploaddata(uri, encoding.utf8.getbytes(requestdata));             }     }     catch (exception ex)     {         // log exceptions ...     } } 

this doesn't build , gives error:

cannot await 'byte[]'

any ideas how solve this?

you can not await synchrone function, have call [..]async one:

var result = await client.uploaddataasync(uri, encoding.utf8.getbytes(requestdata)); 

the function call returns byte[], of course not awaitable. uploaddataasync returns task<byte[]> instead, 1 want use:

http://msdn.microsoft.com/de-de/library/ms144225(v=vs.110).aspx

edit: method seems return void, kind of awaitable, too.. in terms of fire , forget.