AdsConnectionInvokeRpcMethodAsync(IRpcCallableInstance, IRpcMethod, Object, AnyTypeSpecifier, AnyTypeSpecifier, CancellationToken) Method

C#

public Task<ResultRpcMethod> InvokeRpcMethodAsync(
    IRpcCallableInstance symbol,
    IRpcMethod method,
    Object[]? inParameters,
    AnyTypeSpecifier[]? outSpecifiers,
    AnyTypeSpecifier? retSpecifier,
    CancellationToken cancel
)

Parameters

Return Value

Task ResultRpcMethod
A task that represents the asynchronous 'InvokeRpcMethod' operation. The ResultRpcMethod results contains the return value together with the output parameters.

Remarks

The RpcMethod optionally support In-Parameters, Out-Parameters and Return values. Therefore the parameters inParameters are allowed to be empty or NULL.ReturnValue and the ErrorCode of the ADS communication after execution.

Implements

IAdsRpcInvokeInvokeRpcMethodAsync(IRpcCallableInstance, IRpcMethod, Object, AnyTypeSpecifier, AnyTypeSpecifier, CancellationToken)

Exceptions

Example

The following sample shows how to call (Remote Procedures / Methods) within the PLC.

Dynamic Tree Mode

class RpcCallVirtualProgram
{
    /// <summary>
    /// Defines the entry point of the application.
    /// </summary>
    /// <param name="args">The arguments.</param>
    static void Main(string[] args)
    {
    // Get the AdsAddress from command-line arguments
    AmsAddress address = ArgParser.Parse(args);

    using (AdsClient client = new AdsClient())
    {
        //client.Synchronize = false;

        // Connect to the target device
        client.Connect(address);

        SymbolLoaderSettings settings = new SymbolLoaderSettings(SymbolsLoadMode.VirtualTree);
        ISymbolLoader loader = SymbolLoaderFactory.Create(client, settings);

        // Get the Symbols (Dynamic Symbols)

        IStructInstance main = (IStructInstance)loader.Symbols["MAIN"]; // Gets the MAIN Instance of the PLC Program

        // Call a Method that has the following signature (within MAIN Program)
        /*  {attribute 'TcRpcEnable'}
        METHOD PUBLIC M_Add : INT
        VAR_INPUT
            i1 : INT := 0;
            i2 : INT := 0;
        END_VAR 
        */

        short result = (short)main.InvokeRpcMethod("M_Add", new object[] {(short) 3, (short) 4});

        // Call a Method that has no parameter and returns VOID
        main.InvokeRpcMethod("M_Method1", new object[] {});

        //Browsing RpcMethods
        foreach(IRpcMethod method in main.RpcMethods)
        {
        string methodName = method.Name;

        foreach(IRpcMethodParameter parameter in method.Parameters)
        {
            string parameterName = parameter.Name;
            string parameterType = parameter.TypeName;
        }
        }
    }
    }
}

Reference

AdsConnection Class InvokeRpcMethodAsync Overload TwinCAT.Ads Namespace

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