Read/Write primitive values

Reading writing Values from ADS Devices is the most essential part of the communication API. There are several options for communication with your application.

• Accessing by IndexGroup / IndexOffset
• Symbolic access by instance path and optionally use handles for the symbol
• Holding the overall Symbolic information in the SymbolLoader and use easy access via symbol objects.
• Usage the symbolic interface ITcAdsSymbol when complete SymbolLoading by SymbolLoaders is not appropriate.
• Reading / Writing values as .NET managed Types (primitive types or compound primitive types called ANY_TYPES), or complex dynamic types typesafe generated at runtime.

The following section shows the different scenarios as code snippets.

HowTo Read/Write Values

using (TcAdsClient client = new TcAdsClient())
{
    UInt32 valueToRead = 0;
    UInt32 valueToWrite = 42;

    client.Connect(AmsNetId.Local, 851);
    adsClient.WriteAny(0x4020, 0x0, valueToWrite);
    valueToRead = (uint)adsClient.ReadAny(0x4020, 0x0, typeof(UInt32));
}

using (TcAdsClient client = new TcAdsClient())
{
    int varHandle = 0;
    client.Connect(AmsNetId.Local, 851);
    try
    {
    UInt32 valueToRead = 0;
    UInt32 valueToWrite = 42;

    varHandle = client.CreateVariableHandle("MAIN.nCounter");
    adsClient.WriteAny(varHandle, valueToWrite);
    valueToRead = (uint)adsClient.ReadAny(varHandle, typeof(UInt32));
    }
    finally
    {
    // Unregister VarHandle after Use
    client.DeleteVariableHandle(varHandle);
    }
}

using (TcAdsClient client = new TcAdsClient())
{
    UInt32 valueToRead = 0;
    UInt32 valueToWrite = 42;

    client.Connect(AmsNetId.Local, 851);
    adsClient.WriteSymbol("MAIN.nCounter", valueToWrite, false);
    valueToRead = (uint)adsClient.ReadSymbol("MAIN.nCounter", typeof(UInt32),false);
}

using (TcAdsClient client = new TcAdsClient())
{
    UInt32 valueToRead = 0;
    UInt32 valueToWrite = 42;

    client.Connect(AmsNetId.Local, 851);

    ITcAdsSymbol symbol = adsClient.ReadSymbolInfo("MAIN.nCounter");
    adsClient.WriteSymbol(symbol, valueToWrite);
    valueToRead = (uint)adsClient.ReadSymbol(symbol);
}

using (TcAdsClient client = new TcAdsClient())
{
    UInt32 valueToRead = 0;
    UInt32 valueToWrite = 42;

    client.Connect(AmsNetId.Local, 851);

    // Load all Symbols + DataTypes
    ISymbolLoader loader = SymbolLoaderFactory.Create(client, SymbolLoaderSettings.Default);
    Symbol symbol = (Symbol)loader.Symbols["MAIN.nCounter"];

    // Works for ALL Primitive 'ANY TYPES' Symbols
    symbol.WriteValue(valueToWrite); 
    valueToRead = (UInt32)symbol.ReadValue();
}

using (TcAdsClient client = new TcAdsClient())
{
    UInt32 valueToRead = 0;
    UInt32 valueToWrite = 42;

    client.Connect(AmsNetId.Local, 851);

    // Load all Symbols + DataTypes
    // Primitive Parts will be automatically resolved to .NET Primitive types.
    IDynamicSymbolLoader loader = (IDynamicSymbolLoader)SymbolLoaderFactory.Create(client, SymbolLoaderSettings.DefaultDynamic);

    dynamic symbols = loader.SymbolsDynamic;
    dynamic main = symbols.Main;

    // Use typed object to use InfoTips
    DynamicSymbol nCounter = main.nCounter;

    // or to be fullDynamic 
    //dynamic nCounter = main.nCounter;

    // Works for ALL sorts of types (not restricted to ANY_TYPE basing primitive types)
    nCounter.WriteValue(valueToWrite);
    valueToRead = (uint)nCounter.ReadValue();
}