Ignition Perspective Tag Value Change script help

Ignition
,
1

I am trying to use a script that will pick out parts of a string entered and send those parts to another tag. I was able to get this script working on our Dev server:

def valueChanged(tag, tagPath, previousValue, currentValue, initialChange, missedEvents):
	if currentValue.value != '':
		data = str(currentValue)
		import re
		m = re.search('.*PN: (.+)BN:\\s*([0-9]{7}).*', data)
		###system.tag.writeBlocking("[.]JobScan",m.group(0))
		system.tag.writeBlocking("[.]PartNumber",m.group(1))
		system.tag.writeBlocking("[.]BatchNumber",m.group(2))
	else:
		system.tag.writeBlocking("[.]PartNumber",'')
		system.tag.writeBlocking("[.]BatchNumber",'')

but then I transferred it to our production server and it doesn't seem to work now. I tried to switch the tag paths to point to the new tag paths and it still doesn't work:

def valueChanged(tag, tagPath, previousValue, currentValue, 
	if currentValue.value != '':
		data = str(currentValue.value)
		import re
		m = re.search('.*PN: (.+)BN:\\s*([0-9]{7}).*', data)
		###system.tag.writeBlocking("[.]JobScan",m.group(0))
		system.tag.writeBlocking(["[default]E398/E398/JobScanInfo/PartNumber.value"],[m.group(1)])
		system.tag.writeBlocking(["[default]E398/E398/JobScanInfo/BatchNumber.value"],[m.group(2)])
	else:
		system.tag.writeBlocking(["[default]E398/E398/JobScanInfo/PartNumber.value"],[''])
	    system.tag.writeBlocking(["[default]E398/E398/JobScanInfo/BatchNumber.value"],[''])

Am I missing something?
EDIT:
I tried to copy a working value change script from another tag to this one, and it doesn't work. It works perfectly fine for the tag I copied it from, but when I past it into this tags value changed script, it won't write to the other tag. Here is the script that works for one tag but not the other:

	if currentValue.value != '':	
		system.tag.writeBlocking('[default]{ENumber}/{ENumber}/JobScanInfo/PartNumberMem.value', currentValue.value)
2

I have found that it is the

m = re.search('.*PN: (.+)BN:\\s*([0-9]{7}).*', data)

part of the script. Any idea why it would work for our dev gateway and not our production gateway?

3

Your strings aren't what they're supposed to be, so the regex is failing?

Try
print repr(system.tag.readBlocking(["whateverTagThisIs"])[0].value)
In the script console on the production system.

5

I did this and it is printing out the correct value of the tag, except it has a 'u' infront of it for some reason...

image

But this is the same output as the project on our Dev server that is working correctly

6

Is it the escaped \\s after BN?

7

I don't think so. I messed around with that on my project that is working and it is giving me the correct output every time. When I try it on my other gateway, it won't write anything as soon as I put the

m = re.search('.*PN: (.+)BN:\\s*([0-9]{7}).*', data)

line of code.

I was using this code

def valueChanged(tag, tagPath, previousValue, currentValue, initialChange, missedEvents):
	if currentValue.value != '':
		import re
		m = re.search('.*PN: (.+)BN:\s*([0-9]{7}).*', data)
		system.tag.writeBlocking('[default]{ENumber}/{ENumber}/JobScanInfo/PartNumberMem.value', currentValue.value)

starting with just the writeBlocking, then started adding more line by line until it wouldn't print anymore.

Even if I comment out the line, it still stops it from writing until I completely delete it.

8

That just means it's a Unicode string (supporting a wider character set). You shouldn't have to worry about it.

1 Like
9

I have found out that the issue is the {} around the 7, but I am not sure of a work around

10

Oh, wait, are you writing this script out in a UDT?

I think you're getting hit by a bug with parameter referencing; it's attempting to replace the curly brace portion as if it were a UDT parameter.

Try putting your code in the project library (in your gateway scripting project) and calling it from your tag.