How to send return value of function from server to clien?.

[sushilN]

Hi,

I am using .NET based OPC UA SDK. I created one function as Addition and registered it on server side. I can successfully call and provide the input arguments for Addition function from client side. But I am not able to send the result of addition through output argument from server to client. It is always null. I don't understand how to send return value of addition function to client.

Thanks!

[Support Team]

Hello,

Please see the code of the DemoServer. There are Methods defined and implemented.

Code: Select all

        private StatusCode DoMultiply(
            RequestContext context,
            MethodHandle methodHandle,
            IList<Variant> inputArguments,
            List<StatusCode> inputArgumentResults,
            List<Variant> outputArguments)
        {
            double x = inputArguments[0].ToDouble();
            double y = inputArguments[1].ToDouble();

            outputArguments[0] = x * y;

            return StatusCodes.Good;
        }

[sushilN]

Hi,
Thanks for the reply. Yes I am using the same method definition. If we look at the function parameters while debugging, outputArguments is always null. So thats why I am not able to put return value into outputArguments. So It will throw the exception. Even if I initialise outputArguments inside the function and assign the return value, on the client side outputArgument result is always null. So I am not getting how to assign the return value to the outputArguments . I am using examples/ServerGettingStarted/Lesson04.

Thnaks!

[sushilN]

Hi,

I am able to solve the problem. Just need to add OutputArguments UAVariable in XML file.

Thanks.!