nc-webservices-ws_service_message_receive_callback.md

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NC:webservices.WS_SERVICE_MESSAGE_RECEIVE_CALLBACK	WS_SERVICE_MESSAGE_RECEIVE_CALLBACK (webservices.h)	Invoked when a WS_MESSAGE is received on an endpoint configured with a WS_SERVICE_CONTRACT which has defaultMessageHandlerCallback set.	WS_SERVICE_MESSAGE_RECEIVE_CALLBACK WS_SERVICE_MESSAGE_RECEIVE_CALLBACK callback WS_SERVICE_MESSAGE_RECEIVE_CALLBACK callback function [Web Services for Windows] webservices/WS_SERVICE_MESSAGE_RECEIVE_CALLBACK wsw.ws_service_message_receive_callback	wsw\ws_service_message_receive_callback.htm	wsw	2fcd8905-7002-41b8-b947-14d53c889c21	12/05/2018	WS_SERVICE_MESSAGE_RECEIVE_CALLBACK, WS_SERVICE_MESSAGE_RECEIVE_CALLBACK callback, WS_SERVICE_MESSAGE_RECEIVE_CALLBACK callback function [Web Services for Windows], webservices/WS_SERVICE_MESSAGE_RECEIVE_CALLBACK, wsw.ws_service_message_receive_callback	webservices.h		Windows	Windows 7 [desktop apps \| UWP apps]	Windows Server 2008 R2 [desktop apps \| UWP apps]													Windows			19H1	WS_SERVICE_MESSAGE_RECEIVE_CALLBACK webservices/WS_SERVICE_MESSAGE_RECEIVE_CALLBACK	c++	APIRef kbSyntax	UserDefined	WebServices.h	WS_SERVICE_MESSAGE_RECEIVE_CALLBACK

WS_SERVICE_MESSAGE_RECEIVE_CALLBACK callback function

-description

Invoked when a WS_MESSAGE is received on an endpoint configured with a WS_SERVICE_CONTRACT which has defaultMessageHandlerCallback set.

The incoming WS_MESSAGE, the serviceProxy along with other parameters is made available to the callback through WS_OPERATION_CONTEXT.

-parameters

-param context [in]

The context within which this callback is being invoked.

-param asyncContext [in, optional]

Specifies whether the callback can run asynchronously.

-param error [in, optional]

Specifies where additional error information should be stored if the function fails.

-returns

This callback function does not return a value.

-remarks

When defined, callback would disallow all concurrency on a session based channel. If concurrency on a session based channel is desirable an application should not define WS_SERVICE_MESSAGE_RECEIVE_CALLBACK on the WS_SERVICE_CONTRACT.

At the time of the invocation of the callback, service model has performed WsReadMessageStart on the receiving WS_MESSAGE. It is the responsibility of the application implementing WS_SERVICE_MESSAGE_RECEIVE_CALLBACK to process the body and perform WsReadMessageEnd operation.

If the callback fails, the underlying channel is aborted.

See also, UnTypedServiceExample

Examples

Defining a WS_SERVICE_MESSAGE_RECEIVE_CALLBACK

// Method contract for the service
static WS_SERVICE_CONTRACT calculatorContract = 
{
    NULL, 
    NULL, 
    DefaultMessageHandlerCallback, // WS_SERVICE_MESSAGE_RECEIVE_CALLBACK
    NULL
};

Accessing the incoming WS_MESSAGE property

HRESULT CALLBACK MessageRecieved(const WS_OPERATION_CONTEXT* context, const WS_ASYNC_CONTEXT* asyncContext, WS_ERROR* error)
{
    :
    hr = WsGetOperationContextProperty(context, WS_OPERATION_CONTEXT_PROPERTY_INPUT_MESSAGE, &requestMessage, sizeof(requestMessage), NULL, error);
    :
}