Re: Newbie help - test for data type

Jonathan Bowlas wrote:
Hi Listers,

I have a requirement to test for a data type could someone tell me if this
is possible in python?

Basically I have a ZPT in Zope that users can select checkboxes in a form
which pass arguments for a python function, however if there is only one
checkbox selected it is passed as a string whereas more than one checkbox is
passed as a list. Therefore if my function is required to perform an action
based on each argument passed in the list the function works correctly but
if it is passed as a string nothing happens.

You need the isinstance() function. For example you can use
isinstance(selecteddeptcodes, list) to test if your variable is a list. If you want to test the other way round use isinstance(selecteddeptcodes, str) if your variable is a string, isinstance(selecteddeptcodes, unicode) if it's a unicode string or isinstance(selecteddeptcodes, basestring) to test if it's a string or unicode string. Read more about this function and the types to test for in http://docs.python.org/lib/built-in-funcs.html.

If you already have the code for a list argument I'd check if it's not a list and then turn it into a list:


if not isintance(selecteddeptcodes, list):
selecteddeptcodes = [selecteddeptcodes]



Bye,
Dennis
.

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