find xml element based on its attribute and change its value

Question

I am using python xmlElementTree and want to assign or modify a xml element value based on its attribute. Can somebody give me an idea how to do this?

For example: Here

Answer 1

You can access the attribute value as this:

from elementtree.ElementTree import XML, SubElement, Element, tostring

text = """

    
        
        
        
    

    
        
        
    

"""

elem = XML(text)
for node in elem.find('phoneNumbers'):
    print node.attrib['topic']
    # Create sub elements
    if node.attrib['topic']=="sys/phoneNumber/1":
        tag = SubElement(node,'TagName')
        tag.attrib['attr'] = 'AttribValue'

print tostring(elem)

forget to say, if your ElementTree version is greater than 1.3, you can use XPath:

elem.find('.//number[@topic="sys/phoneNumber/1"]')

http://effbot.org/zone/element-xpath.htm

or you can use this simple one:

for node in elem.findall('.//number'):
    if node.attrib['topic']=="sys/phoneNumber/1":
        tag = SubElement(node,'TagName')
        tag.attrib['attr'] = 'AttribValue'