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Array reading error (VT_R4)

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29 Nov 2013 14:53 #1574 by Gardoni
Replied by Gardoni on topic Array reading error (VT_R4)
Hello.
Code is very simplyl, because we are just testing your product before eventually purchase it.

private void button1_Click(object sender, EventArgs e)
{
EasyDAClient client = new EasyDAClient();
object p = new object();
Stopwatch sw = new Stopwatch();

sw.Start();

// Array of VT_I4, reading OK
p = client.ReadItemValue("", "OPCTestLab.OPCAnalyzer.1", "InjectPC.IdraSystem.Data.ExtraParameters1");

// Array of VT_R4, error
p = client.ReadItemValue("", "OPCTestLab.OPCAnalyzer.1", "InjectPC.IdraSystem.Data.ExtraParameters");


MessageBox.Show(sw.ElapsedMilliseconds.ToString());
sw.Reset();
}

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29 Nov 2013 14:40 #1573 by support
Replied by support on topic Array reading error (VT_R4)
Interesting. I do not see the error, or anything wrong, in the client-server communication.
And, I have tried the similar thing with out simulation server, and it can read arrays of VT_R4 well.


Would you mind sharing the relevant part of your source code? Including variable declarations.

Thank you

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29 Nov 2013 13:09 #1572 by Gardoni
Replied by Gardoni on topic Array reading error (VT_R4)
Hello. OPCLabs1.* are the traces of my C# app.
It should contain the error I wrote before.
OPCLabs2.txt is the trace of ICONICS OPCDataSpy
The answer is yes, it is written in c# so you can move it.
BR
Davide Gardoni
Attachments:

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29 Nov 2013 08:51 #1571 by support
Replied by support on topic Array reading error (VT_R4)
I suspect that this might be a server issue. In order to determine the real reason, may I ask you to use OPC Analyzer and collect logs of the communication
  • using the ICONICS OPC DataSpy
  • using your application written with QuickOPC

Instructions: www.opclabs.com/download/file/160-QuickOPC-1-How%20to%20use%20OPC%20Analyzer?start=20

The OPC Analyzer download: www.opclabs.com/files/transient/20131129/OPCAnalyzer%201.03.1014.msi

Also, is your app written in C#? If so, I will move this thread under QuickOPC.NET where it belongs.

Best regards

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28 Nov 2013 13:39 #1569 by Gardoni
Hello. We are testing Array Reading from an "Iconics OPC Server Toolkit" compiled OPCServer. Its name is Idra.runtimeDA. Basically reading a VT_I4 array is working using
p = client.ReadItemValue("", "Idra.runtimeDA", "InjectPC.IdraSystem.Data.ExtraParameters1");
where p is an object and ExtraParameters1 is an array of VT_I4
If I try to read
p = client.ReadItemValue("", "Idra.runtimeDA", "InjectPC.IdraSystem.Data.ExtraParameters");
where ExtraParameters is an array of VT_R4
I get this error: InnerException is "Specified array was not of the expected type"
I can read both arrays succesfully with a standalone OPC Client (see attached picture), so I need your help.
Davide Gardoni
Idra srl
Attachments:

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