object --+
         |
        ObjectifiedElementProxy

How to access xml tag

.

such as root.element.name

[]

such as root['element']['name']

hybrid

such as root['element'].name

note

The tag can only be accessed by [] when it is one of the reserved keywords. Tag not in the xml tree can be accessed directly. A new tag will be created. No exceptions will be raised.

How to access xml tag's attributes

[]

.attrib['style'], an exception will be raised when style dos'nt exist. .attrib['style'] = 'big'

.get/set

.attrib.get( 'style', None ) .attrib.set( 'style', 'big' )

How to access class attributes and methods

.

attributes are reserved keywords and they can only be accessed by this way, for example .pyval .text .insert etc. or they are considered xml tags rather than attributes.

Reserved keywords

The following keywords are used as methods or attributes' names.

pyval : returns the python value carried by leaf tag. read-only.

text : returns leaf tag's text content. read-only.

obj : returns ObjectifiedElement object referenced by this class instance. read-only.

tag : returns tag names. can be modified by . way such as *.tag='newTagName'. readable and writable.

attrib : returns tag attributes dict. readable and writeable.

parent : returns parent node. read-only.

children : returns all children's list. read-only.

len : returns the number of children.

insert : insert a child node at the specified position.

remove : remove a child node at the specified position.

index : returns the position of the specified object.

swap : swap two nodes' position.

Examples

create a brand new xml:

>>> p = ObjectifiedElmentProxy( rootag='Person' )
>>> p.name = 'peter'
>>> p.age = 13
>>> print( p )
<Person>
    <name>peter</name>
    <age>13</age>
</Person>

create from xml string:

>>> p = ObjectifiedElementProxy( xmlStr="<Person><name>peter</name><age>13</age></Person>" )
>>> print( p )
<Person>
    <name>peter</name>
    <age>13</age>
</Person>

multiple levels examples:

>>> r = ObjectifiedElementProxy()
>>> r.person.name = 'jack'
>>> r.person.age = 10
>>> print( r )
<root>
    <person>
        <name>jack</name>
        <age>10</age>
    </person>
</root>

to insert child like '<person><name>peter</name><age>13</age></person>':

>>> r.insert( 'person' )('name','peter')('age',13)

>>> p = r('person').person[-1]
>>> p.name = 'david'
>>> p.age = 16
>>> print( r )
<root>
    <person>
        <name>jack</name>
        <age>10</age>
    </person>
    <person>
        <name>peter</name>
        <age>13</age>
    </person>
    <person>
        <name>david</name>
        <age>16</age>
    </person>
</root>

>>> print( r.station[1].name.pyval )
peter

Notes

xml attrib names and tag names are case insensitive.

Nodes with text attribute are called leaf nodes. Theoretically, leaf nodes should not have children, but not required.

>>> p=ObjectifiedElementProxy( rootag='Person' )
>>> p( 'name', pyval='jack' )('age', pyval=13 )
>>> print( p )
<Person>
        <name py:pytype="str">jack</name>
        <age py:pytype="int">13</age>
</Person>

find elements list in accordance with path.

Arguments
---------
path : str
    please refer to lxml.objectify.ObjectifiedElement.xpath.

Returns
-------
list
    a list of ObjectifiedElementProxy instance.


Xpath grammer review
--------------------

==========  ===========
expression  description
==========  ===========   
nodename    to select all children of the node name
/           select from root node.    
//          select from current node
.           select the current code.   
..          select the parent node of the current node.
@           select attrib.
[]          condition
text()      tag text
*           arbitrary node
==========  ============