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Silverlight asynchronous WebService call with UI-thread syncronization dispatcher
You can use this code to make a async WebRequest from Silverlight to update ViewModel.
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|
//#r "System.Runtime.Serialization"
//#r "FSharp.PowerPack"
open Microsoft.FSharp.Control.WebExtensions
open System
open System.Runtime.Serialization
open System.Runtime.Serialization.Json
open System.Net
open System.IO
let internal fetchAsync (url : Uri) trigger =
let req = WebRequest.CreateHttp url
req.CookieContainer <- new CookieContainer()
let asynccall =
async{
try
let! res = req.AsyncGetResponse()
use stream = res.GetResponseStream()
use reader = new StreamReader(stream)
let! rdata = reader.AsyncReadToEnd()
callresult <- rdata //some processing like unjson here...
trigger "" |> ignore
with
| _ as ex -> //for debug
failwith(ex.ToString())
}
asynccall |> Async.StartImmediate
//UI-thread syncronization with Dispatcher
let trigger _ =
let update _ = x.MyViewModelProperty <- callresult
System.Windows.Deployment.Current.Dispatcher.BeginInvoke(new Action(update)) |> ignore
let service = new Uri("http://...", UriKind.Absolute)
fetchAsync service trigger
|
namespace Microsoft
namespace Microsoft.FSharp
namespace Microsoft.FSharp.Control
module WebExtensions
from Microsoft.FSharp.Control
namespace System
namespace System.Runtime
namespace System.Runtime.Serialization
namespace System.Net
namespace System.IO
val internal fetchAsync : url:Uri -> trigger:(string -> 'a) -> unit
Full name: Script.fetchAsync
val url : Uri
Multiple items
type Uri =
new : uriString:string -> Uri + 5 overloads
member AbsolutePath : string
member AbsoluteUri : string
member Authority : string
member DnsSafeHost : string
member Equals : comparand:obj -> bool
member Fragment : string
member GetComponents : components:UriComponents * format:UriFormat -> string
member GetHashCode : unit -> int
member GetLeftPart : part:UriPartial -> string
...
Full name: System.Uri
--------------------
Uri(uriString: string) : unit
Uri(uriString: string, uriKind: UriKind) : unit
Uri(baseUri: Uri, relativeUri: string) : unit
Uri(baseUri: Uri, relativeUri: Uri) : unit
val trigger : (string -> 'a)
val req : obj
type WebRequest =
inherit MarshalByRefObject
member Abort : unit -> unit
member AuthenticationLevel : AuthenticationLevel with get, set
member BeginGetRequestStream : callback:AsyncCallback * state:obj -> IAsyncResult
member BeginGetResponse : callback:AsyncCallback * state:obj -> IAsyncResult
member CachePolicy : RequestCachePolicy with get, set
member ConnectionGroupName : string with get, set
member ContentLength : int64 with get, set
member ContentType : string with get, set
member Credentials : ICredentials with get, set
member EndGetRequestStream : asyncResult:IAsyncResult -> Stream
...
Full name: System.Net.WebRequest
Multiple items
type CookieContainer =
new : unit -> CookieContainer + 2 overloads
member Add : cookie:Cookie -> unit + 3 overloads
member Capacity : int with get, set
member Count : int
member GetCookieHeader : uri:Uri -> string
member GetCookies : uri:Uri -> CookieCollection
member MaxCookieSize : int with get, set
member PerDomainCapacity : int with get, set
member SetCookies : uri:Uri * cookieHeader:string -> unit
static val DefaultCookieLimit : int
...
Full name: System.Net.CookieContainer
--------------------
CookieContainer() : unit
CookieContainer(capacity: int) : unit
CookieContainer(capacity: int, perDomainCapacity: int, maxCookieSize: int) : unit
val asynccall : Async<unit>
val async : AsyncBuilder
Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.async
val res : obj
val stream : IDisposable
val reader : StreamReader
Multiple items
type StreamReader =
inherit TextReader
new : stream:Stream -> StreamReader + 9 overloads
member BaseStream : Stream
member Close : unit -> unit
member CurrentEncoding : Encoding
member DiscardBufferedData : unit -> unit
member EndOfStream : bool
member Peek : unit -> int
member Read : unit -> int + 1 overload
member ReadLine : unit -> string
member ReadToEnd : unit -> string
...
Full name: System.IO.StreamReader
--------------------
StreamReader(stream: Stream) : unit
StreamReader(path: string) : unit
StreamReader(stream: Stream, detectEncodingFromByteOrderMarks: bool) : unit
StreamReader(stream: Stream, encoding: Text.Encoding) : unit
StreamReader(path: string, detectEncodingFromByteOrderMarks: bool) : unit
StreamReader(path: string, encoding: Text.Encoding) : unit
StreamReader(stream: Stream, encoding: Text.Encoding, detectEncodingFromByteOrderMarks: bool) : unit
StreamReader(path: string, encoding: Text.Encoding, detectEncodingFromByteOrderMarks: bool) : unit
StreamReader(stream: Stream, encoding: Text.Encoding, detectEncodingFromByteOrderMarks: bool, bufferSize: int) : unit
StreamReader(path: string, encoding: Text.Encoding, detectEncodingFromByteOrderMarks: bool, bufferSize: int) : unit
val rdata : obj
val ignore : value:'T -> unit
Full name: Microsoft.FSharp.Core.Operators.ignore
val ex : exn
val failwith : message:string -> 'T
Full name: Microsoft.FSharp.Core.Operators.failwith
Exception.ToString() : string
Multiple items
type Async
static member AsBeginEnd : computation:('Arg -> Async<'T>) -> ('Arg * AsyncCallback * obj -> IAsyncResult) * (IAsyncResult -> 'T) * (IAsyncResult -> unit)
static member AwaitEvent : event:IEvent<'Del,'T> * ?cancelAction:(unit -> unit) -> Async<'T> (requires delegate and 'Del :> Delegate)
static member AwaitIAsyncResult : iar:IAsyncResult * ?millisecondsTimeout:int -> Async<bool>
static member AwaitTask : task:Task<'T> -> Async<'T>
static member AwaitWaitHandle : waitHandle:WaitHandle * ?millisecondsTimeout:int -> Async<bool>
static member CancelDefaultToken : unit -> unit
static member Catch : computation:Async<'T> -> Async<Choice<'T,exn>>
static member FromBeginEnd : beginAction:(AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg:'Arg1 * beginAction:('Arg1 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg1:'Arg1 * arg2:'Arg2 * beginAction:('Arg1 * 'Arg2 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg1:'Arg1 * arg2:'Arg2 * arg3:'Arg3 * beginAction:('Arg1 * 'Arg2 * 'Arg3 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromContinuations : callback:(('T -> unit) * (exn -> unit) * (OperationCanceledException -> unit) -> unit) -> Async<'T>
static member Ignore : computation:Async<'T> -> Async<unit>
static member OnCancel : interruption:(unit -> unit) -> Async<IDisposable>
static member Parallel : computations:seq<Async<'T>> -> Async<'T []>
static member RunSynchronously : computation:Async<'T> * ?timeout:int * ?cancellationToken:CancellationToken -> 'T
static member Sleep : millisecondsDueTime:int -> Async<unit>
static member Start : computation:Async<unit> * ?cancellationToken:CancellationToken -> unit
static member StartAsTask : computation:Async<'T> * ?taskCreationOptions:TaskCreationOptions * ?cancellationToken:CancellationToken -> Task<'T>
static member StartChild : computation:Async<'T> * ?millisecondsTimeout:int -> Async<Async<'T>>
static member StartChildAsTask : computation:Async<'T> * ?taskCreationOptions:TaskCreationOptions -> Async<Task<'T>>
static member StartImmediate : computation:Async<unit> * ?cancellationToken:CancellationToken -> unit
static member StartWithContinuations : computation:Async<'T> * continuation:('T -> unit) * exceptionContinuation:(exn -> unit) * cancellationContinuation:(OperationCanceledException -> unit) * ?cancellationToken:CancellationToken -> unit
static member SwitchToContext : syncContext:SynchronizationContext -> Async<unit>
static member SwitchToNewThread : unit -> Async<unit>
static member SwitchToThreadPool : unit -> Async<unit>
static member TryCancelled : computation:Async<'T> * compensation:(OperationCanceledException -> unit) -> Async<'T>
static member CancellationToken : Async<CancellationToken>
static member DefaultCancellationToken : CancellationToken
Full name: Microsoft.FSharp.Control.Async
--------------------
type Async<'T>
Full name: Microsoft.FSharp.Control.Async<_>
static member Async.StartImmediate : computation:Async<unit> * ?cancellationToken:Threading.CancellationToken -> unit
val trigger : 'a -> unit
Full name: Script.trigger
val update : ('b -> 'c)
namespace System.Windows
namespace System.Deployment
Multiple items
type Action =
delegate of unit -> unit
Full name: System.Action
--------------------
type Action<'T> =
delegate of 'T -> unit
Full name: System.Action<_>
--------------------
type Action<'T1,'T2> =
delegate of 'T1 * 'T2 -> unit
Full name: System.Action<_,_>
--------------------
type Action<'T1,'T2,'T3> =
delegate of 'T1 * 'T2 * 'T3 -> unit
Full name: System.Action<_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 -> unit
Full name: System.Action<_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 -> unit
Full name: System.Action<_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 -> unit
Full name: System.Action<_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 -> unit
Full name: System.Action<_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9,'T10> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 * 'T10 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9,'T10,'T11> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 * 'T10 * 'T11 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9,'T10,'T11,'T12> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 * 'T10 * 'T11 * 'T12 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9,'T10,'T11,'T12,'T13> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 * 'T10 * 'T11 * 'T12 * 'T13 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9,'T10,'T11,'T12,'T13,'T14> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 * 'T10 * 'T11 * 'T12 * 'T13 * 'T14 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9,'T10,'T11,'T12,'T13,'T14,'T15> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 * 'T10 * 'T11 * 'T12 * 'T13 * 'T14 * 'T15 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_,_,_,_,_,_,_>
--------------------
type Action<'T1,'T2,'T3,'T4,'T5,'T6,'T7,'T8,'T9,'T10,'T11,'T12,'T13,'T14,'T15,'T16> =
delegate of 'T1 * 'T2 * 'T3 * 'T4 * 'T5 * 'T6 * 'T7 * 'T8 * 'T9 * 'T10 * 'T11 * 'T12 * 'T13 * 'T14 * 'T15 * 'T16 -> unit
Full name: System.Action<_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_>
val service : Uri
Full name: Script.service
type UriKind =
| RelativeOrAbsolute = 0
| Absolute = 1
| Relative = 2
Full name: System.UriKind
field UriKind.Absolute = 1
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