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Problem with mapping arrays

03 Aug 2018 06:18 #6579 by support
Replied by support on topic Problem with mapping arrays
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02 Aug 2018 19:53 #6575 by ab

I have a problem with reading tables from the OPC UA server.
I do not know why, but if I use mapping objects, their vaules are always zeros after reading from opc.
If I read them directly, the values in the array are valid.
What am I doing wrong?

The following example illustrates the problem.
UAClientMapper mapper = new UAClientMapper();
TestArray device = new TestArray { BrowswerPath = "ObjectsFolder]/PLC1500/Device1/Program_blocks/UM01_przyklad/Data/UM01_PackTags" };
UANodeDescriptor uANodeDescriptor = new UANodeDescriptor
      BrowsePath = UABrowsePath.Parse(device.BrowswerPath, "KEPServerEX")
UAEndpointDescriptor uAEndpointDescriptor = new UAEndpointDescriptor("opc.tcp://");
var uaNodeElementCollection = mapper.Client.BrowseDataNodes(uAEndpointDescriptor);
mapper.Map(device, new UAMappingContext
      EndpointDescriptor = uAEndpointDescriptor,
      NodeDescriptor = uANodeDescriptor,
      MonitoringParameters = 1000
var easyUAClient = new EasyUAClient { Isolated = true };
var a = easyUAClient.Read(uAEndpointDescriptor, "nsu=KEPServerEX;ns=2;s=PLC1500.Device1.Program_blocks.UM01_przyklad.Data.UM01_PackTags.Admin.ModeCumulativeTime");
var b = device.ModeCumulativeTime;
public class TestArray : IBrowsePath
    public TestArray()
         ModeCumulativeTime = new long[6];
    public long[] ModeCumulativeTime { get; set; }
    public string BrowswerPath { get; set; }

After executing the code, the values for the variable "a" are for example [1, 2, 3, 10, 100, 5] and for "b" it are always [0, 0.0,0,0,0], why? It's the same array in opc.

What should mapping look like if we have a two-dimensional array? Can I map an array of objects, for example: MyClass[];?

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