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Extract value of attribute node via XPath

How can I extract the value of an attribute node via XPath?

A sample XML file is:

<parents name='Parents'>
  <Parent id='1' name='Parent_1'>
    <Children name='Children'>
      <child name='Child_2' id='2'>child2_Parent_1</child>
      <child name='Child_4' id='4'>child4_Parent_1</child>
      <child name='Child_1' id='3'>child1_Parent_1</child>
      <child name='Child_3' id='1'>child3_Parent_1</child>
    </Children>
  </Parent>
  <Parent id='2' name='Parent_2'>
    <Children name='Children'>
      <child name='Child_1' id='8'>child1_parent2</child>
      <child name='Child_2' id='7'>child2_parent2</child>
      <child name='Child_4' id='6'>child4_parent2</child>
      <child name='Child_3' id='5'>child3_parent2</child>
    </Children>
  </Parent>
</parents>

So far I have this XPath string:

//Parent[@id='1']/Children/child[@name]  

It returns only child elements, but I would like to have the value of the name attribute.

For my sample XML file, here's what I'd like the output to be:

Child_2
Child_4
Child_1
Child_3
Possible duplicate of Getting attribute using XPath

R
Rory O'Kane
//Parent[@id='1']/Children/child/@name 

Your original child[@name] means an element child which has an attribute name. You want child/@name.


I agree, the question was how to get the value of the attribute
What if i would like to extract only the value/description/data present in between the tags ....
F
Flow

To get just the value (without attribute names), use string():

string(//Parent[@id='1']/Children/child/@name)

The fn:string() fucntion will return the value of its argument as xs:string. In case its argument is an attribute, it will therefore return the attribute's value as xs:string.


With xqilla it was necessary to call xs:string. I wonder why.
@krlmlr Probably xs is the namespace prefix for the XPath functions. So they are not mixed up with others.
LOL. This is the only answer that actually answers the question. +1
This will provide only the first hit in xmllint
What if I have a list of attributes and I need their values? string() seems to return just the first value.
a
abatishchev

You should use //Parent[@id='1']/Children/child/data(@name)

The attributes can not be serialized so you can't return them in an xml looking result. What you need to do is obtain the data from the attribute using data() function.


data() function on an attribute gives the error "XPath error : Invalid expression" in xmllint.
V
Vinod Srivastav

As answered above:

//Parent[@id='1']/Children/child/@name 

will only output the name attribute of the 4 child nodes belonging to the Parent specified by its predicate [@id=1]. You'll then need to change the predicate to [@id=2] to get the set of child nodes for the next Parent.

However, if you ignore the Parent node altogether and use:

//child/@name

you can select name attribute of all child nodes in one go.

name="Child_2"
name="Child_4"
name="Child_1"
name="Child_3"
name="Child_1"
name="Child_2"
name="Child_4"
name="Child_3"

S
Soner Gönül
//Parent/Children[@  Attribute='value']/@Attribute

This is the case which can be used where element is having 2 attribute and we can get the one attribute with the help of another one.


E
Ed Bangga

for all xml with namespace use local-name()

//*[local-name()='Parent'][@id='1']/*[local-name()='Children']/*[local-name()='child']/@name 

a
abatishchev

@ryenus, You need to loop through the result. This is how I'd do it in vbscript;

Set xmlDoc = CreateObject("Msxml2.DOMDocument")
xmlDoc.setProperty "SelectionLanguage", "XPath"
xmlDoc.load("kids.xml")

'Remove the id=1 attribute on Parent to return all child names for all Parent nodes
For Each c In xmlDoc.selectNodes ("//Parent[@id='1']/Children/child/@name")
    Wscript.Echo c.text
Next

佚名

Here is the standard formula to extract the values of attribute and text using XPath-

To extract attribute value for Web Element- elementXPath/@attributeName To extract text value for Web Element- elementXPath/text()

In your case here is the xpath which will return

//parent[@name='Parent_1']//child/@name

It will return:

Child_2
Child_4
Child_1
Child_3