解析 XML 时检查 None 值

Question

I am parsing a XML file. I need to check for series_id field. But i am unable to find a condition where the value is not there. Tried None, len(has_series) = 0 but it never gives me a value. Even i tried to check for False and " ". But not able to validate the condition.

My Snippet below

has_series = program.xpath('props/*[@title="Series_ID"]')
if has_series is None:
    print "None Value"
if len(has_series) ==0:
    print "Zero value"
if has_series == False:
    series_id = "N"
else:
    series_id = has_series[0].text
    print series_id

Part from the XML without has_series

<para352 title="Series_ID"></para352>

I need to find a check for no value. The output comes like this.

Processing: /tmp/rosh/dummy/30000000550321045_2019_10_22T19_49_13Z.xml


Processing: /tmp/rosh/dummy/30000000550324403_2019_10_22T19_49_13Z.xml


Processing: /tmp/rosh/dummy/30000000550324407_2019_10_22T19_49_13Z.xml


Processing: /tmp/rosh/dummy/E30000001555205318_2019_10_09T12_19_38Z.xml
XN016663
Processing: /tmp/rosh/dummy/E30000001555205320_2019_10_09T12_19_38Z.xml
XN016663
Processing: /tmp/rosh/dummy/E30000001555332469_2019_10_09T12_19_38Z.xml
XN016663

wherever the values are picked, script displays it properly. But i need to validate against a non value condition.

Answer 1

通过使用 series_id.isalnum()，我可以检查空值。