Question

I have an XML snippet like:

<CharacterBlock MinVal="-10.000000"  MaxVal="15.000000" Active="1">

and I need to parse the minimum and maximum floating point values. I can’t use an XML parser like ElementTree, so I’m forced to use a regular expression.

I have written the following Python regex:

re.compile('<CharacterBlock MinVal="(?P<MinVal>-?[0-9]*\.?[0-9]*)" MaxVal="(?P<MaxVal>-?[0-9]*\.?[0-9]*)" .*?>', re.DOTALL)

which works for the above snippet. But since the XML attributes are like a dictionary, their order is not guaranteed, and sometimes I receive a snippet like:

<CharacterBlock Active="0" MaxVal="-15.000000" MinVal="-100.000000">

How do I handle this case where the order of the groups I want to match is not fixed?

Answer 1

can you get the two values separately ? like:

In [2]: s='<CharacterBlock Active="0" MaxVal="-15.000000" MinVal="-100.000000">'
In [3]: import re
In [4]: manReg='(?<=MaxVal=")[^"]*'
In [5]: minReg='(?<=MinVal=")[^"]*'

In [6]: re.findall(minReg, s)
Out[7]: ['-100.000000']

In [8]: re.findall(maxReg, s)
Out[9]: ['-15.000000']