Hello,
WinCC OA Best Practice Question Here.
I have recently noticed the dpid datapoint element type in the para, and have started using it when I need to store a datapoint inside another element.
However, I have noticed that when you delete the linked datapoint the dpid is reduced to just the bracketed section {e.g (Type: 37 Sys: 1 Dp: 94 El: 1 : 0..0) } and I think this could cause unusual behaviour in any linked scripts, it would be better if it just returned an empty string.
So I just wanted to ask whether it is better to use the dpid type or better to just store the datapoint name as a string and check that it exists inside scripts? And any other pros and cons of this type?
Regards,
Louis
Dpid element type
- Gertjan van Schijndel
- Posts:634
- Joined: Mon Aug 02, 2010 10:37 am
Re: Dpid element type
In both cases 'dpExists' should be used to check if the datapoint actually exists.
The benefit of the dpid type is that it is actually a datapoint identifier and you can see in the para that the datapoint element does not exist (anymore). But the main benefit is with drivers, which normally do not have a complete datapoint container, so it does not require additional handling for conversion to/from strings.
The benefit of the dpid type is that it is actually a datapoint identifier and you can see in the para that the datapoint element does not exist (anymore). But the main benefit is with drivers, which normally do not have a complete datapoint container, so it does not require additional handling for conversion to/from strings.