Xpath select all child nodes

I try this:

var selectNode = htmlDoc.GetElementbyId("onoffaci");   
var nodes = selectNode.SelectNodes("option::*"); 

but I get error that xpath has invalid token. What is bad?

The obvious problem is the use of

option::*

option::* means: All nodes in the "option" axis. However there is no "option axis in XPath"

You want:

option

This selects all option elements that are children of the current node.

You can write this in a single XPath expression and omit the getElementbyId() call:

//select[@id='onoffaci']/option

For example:

    <option value="**a_0**">**VÅ¡etci**</option>

I need get value (a_0) and text VÅ¡etci

Use:

    //select[@id='onoffaci']/option/@value 
|
    //select[@id='onoffaci']/option/text()

This selects all value attributes of all option elements that are children of all select elements in the XML document that have an id attribute with value 'onoffaci' and also all text nodes of all option elements that are children of all select elements in the XML document that have an id attribute with value 'onoffaci'.

You will need to iterate the results to get the @value and text() for each option element.

Or:

    //select[@id='onoffaci']/option[1]/@value 
|
    //select[@id='onoffaci']/option[1]/text()

Here you use the observation that the option element you are interested in is the first option child of its parent — now this selects only the value attribute and the text nodes of the wanted option element.