Hello, no problem.

GetLowerBound and GetUpperBound will work on any array-typed variable, so I believe you do not need any additional namespace declaration for that. So if you have g.
the you can do value.GetLowerBound(0) and value.GetUpperBound(0) - but not if 'value' was declared as scalar ("object value = ......");

Same with the .Cast<> etc. - it works on arrays (well, it works on any IEnumerable) - but not on scalars.

Referring to the screenshot you have sent, converting to array of Int32, would be done something like

(I have not tested it, but hope it is right).
But I would expect you obtain the bounds before doing the .Cast<> - because the code above would "normalize" the lower bound to 0, and shift the upper bound if needed. This may be good thing (if you want to be sure that the lower bounds is always 0, for further processing), or a bad thing (if you wanted to know what the lower bound actually was, in the array delivered by the server).

If you later want to post images (screenshots), please do so using the "Attachments" button below the forum editor box.

Best regards

Hello.

Regarding the first issue: You can either convert the whole array, or you can process it element by element (as you are doing in the second example) and do the conversion on each element. Converting the whole array can be done in multiple ways, I personally would prefer something like
(where Cast<> and ToArray are from the System.Linq namespace).

Regarding the second issue, I would also intuitively expect that the low array boud is 0 and the high array bound is 1, so at first glance your code looks correct to me. But we cannot know for sure what the server has returned. Please inspect what the bounds of the returned array are, by retrieving its .GetLowerBound(0) and .GetUpperBound(0).

Regards

The value is not a string. You are displaying the result object *as a string*, and QuickOPC formats it, and in the process it only shows several first elements of long arrays, so that the resulting string is readable by humans.

The actual value is array of integers, and there is the whole array present, not just part of it. If you write code to get the length of the array, you will see that it is much longer, and you can get all its elements by index.

Regards

Hello.

There are basically three options to read an array element in OPC UA:

1. Read the whole array, and then extract the desired element(s) by the means of the programming language or tool you are using. Advantage: It always works. Disadvantage: It is ineffective with larger arrays.

2. Pass IndexRange as part of the read request. The server then extracts the requested element(s) and returns only them to the caller. This is the preferred method. Advantage: It is efficient. Disadvantage: Not all OPC UA servers support it.

3. Use some server-specific means of accessing arrays elements. That is, some servers expose the array, and then, also additional nodes (with different Node IDs) for individual elements of the array. Disadvantage: Only works with specific server, and you need to know how (from the server documentation).

What you have attempted to do looks like method #3. With this I can offer no help, because it depends on the server. It is unlikely to work with integer Node IDs. Such servers usually expose string Node IDs (those with "s="), which then allow to put in the syntax they have chosen. Most likely your server does not support it anyway, so you won't be able to find the syntax at all.

If your arrays are small, go with method #1, it's the easiest.

If they are not, go for method #2 (and hope that the server support it; if not, you'll have to revert to #1). For it, first read this: opclabs.doc-that.com/files/onlinedocs/QuickOpc/Latest/User%2...tml#Index%20Range%20Lists.html .

The examples provided are currently in C# and VB.NET, but the principles are the same in VBA. But because there are no method overload in COM, you'll have to use ReadMultipleValues, and pass in the "argument" objects, and also construct the UAIndexRangeList object from the scratch (and not using helper static methods like .OneDimension, because there are no static methods in COM). If you run into problems, let me know and I wil either advise, or prepare the example in VBA.

S pozdravem