Got OctetString - how to convert data to C string or std::string?

By latonita , 18 September, 2024
Forums
Gurux.DLMS

Hi.
I'm getting data from the meter, it is the manufacturer name.

7E.A0.22.41.03.74.F7.D0.E6.E7.00.C4.01.C1.00.09.10.45.6E.65.72.67.6F.6D.65.72.61.00.00.00.00.00.00.19.92.7E

So it has OctetString
<Data>
<OctetString Value="456E6572676F6D657261000000000000" />
</Data>

This is a hex view of a string "Energomera".

I used cl_updateValue(), then I did var_toString() and what I got is same hex string but separated by spaces.

So I had to do stupid thing and manually convert hex view to null terminated C string

I believe there is a proper way to get proper bytes out of this hex-octet-string.
How do I properly get this octet string converted to bytes?

Thank you.

Kurumi

2 years 1 month ago

HI,

The easiest way to show this as a string is cast it to the char*.

dlmsVARIANT* value = //Get Value.
//Add '\0'
bb_setInt8(value->byteArr, 0);
const char* str = value->byteArr->data;
//Remove '\0'
--value->byteArr->size

BR,
Mikko

latonita

2 years 1 month ago

Thank you! This works perfect. I didn't notice there is raw-bytes array available.