How to use the "translate" Xpath function on a node-set

xpath

25,424

Solution 1

I know I can find-replace a single item using this xpath
/xmldoc/items/item[1]/translate(text(),'-','')
Which will return
"abc"
however, how do I do this for the entire set?

This cannot be done with a single XPath 1.0 expression.

Use the following XPath 2.0 expression to produce a sequence of strings, each being the result of the application of the translate() function on the string value of the corresponding node:

/xmlDoc/items/item/translate(.,'-', '')

Solution 2

The translate function accepts in input a string and not a node-set. This means that writing something like:

"translate(/xmlDoc/items/item/text(),'-','')"

"translate(/xmlDoc/items/item,'-','')"

will result in a function call on the first node only (item[1]).

In XPath 1.0 I think you have no other chances than doing something ugly like:

"concat(translate(/xmlDoc/items/item,'-',''),
 translate(/xmlDoc/items/item[2],'-',''))"

Which is privative for a huge list of items and returns just a string.

In XPath 2.0 this can be solved nicely using for expressions:

  "for $item in /xmlDoc/items/item  
    return replace($item,'-','')"

Which returns a sequence type:

abc cde

PS Do no confuse function calls with location paths. They are different kind of expressions, and in XPath 1.0 can not be mixed.

25,424

Author by

Eran Medan

CTO at arnica.io (I'm hiring!)

Updated on July 09, 2022

Comments

Eran Medan almost 2 years
I have an XML document that contains items with dashes I'd like to strip

e.g.
```
<xmlDoc>
   <items>
      <item>a-b-c</item>
      <item>c-d-e</item>
   <items>
</xmlDoc>
```
I know I can find-replace a single item using this xpath
```
/xmldoc/items/item[1]/translate(text(),'-','')
```
Which will return

"abc"

however, how do I do this for the entire set?

This doesn't work
```
/xmldoc/items/item/translate(text(),'-','')
```
Nor this
```
translate(/xmldoc/items/item/text(),'-','')
```
Is there a way at all to achieve that?
Emiliano Poggi about 13 years

I know that XPath 2.0 path expressions has been improved a lot. But it's new to me to see a function call appended to the path +1. Is this a XPath 2.0 generally applicable function call syntax? It can not be evinced (at first seen) from the specs.
Dimitre Novatchev about 13 years

@empo: Yes. And yes again, I have raised this issue -- this can oncly be deducted by studying the XPath 2.0 grammar rules. The answer I got was that "A W3C Spec isn't a tutorial or a book". :( Perhaps @Michael Kay can comment on this?
Emiliano Poggi about 13 years

Even from grammar rules this is not easily deducible. I'll read them better. Thanks once more.
Arup Rakshit almost 11 years

In this expression /xmlDoc/items/item/translate(.,'-', '') why don't use text() ? asking for knowledge gaining purpose for myself..
Dimitre Novatchev almost 11 years

@Babai, I favor brevity, so I chose the shorter expression.
Arup Rakshit almost 11 years

@DimitreNovatchev Thanks for confirming.. so when . is being used means,it is the context node..right? then on that context node string() function is being applied.. am i correct?
Dimitre Novatchev almost 11 years

@Babai, Yes, because the 1st argument of translate() must be of type xs:string
Arup Rakshit almost 11 years

@DimitreNovatchev Sir - I wrote this to collect "//txt()" the text nodes..,But I want use normalize-space,to strip the texts during the selection,how to do that? please help..!
Dimitre Novatchev almost 11 years

@Babai, This cannot be done with a single XPath 1.0 expression. Also, the test is text() -- not txt() .In XPath 2.0 one can write: //text()/normalize-space(.)
Arup Rakshit almost 11 years

I do have this <div> Hello<br>My name is McOmghall</br> </div>.. and I want the output as Hello My name is McOmghall.. So I used string(//div).. But it is not giving that.. can this be done using xpath1.0 ?