c# Reading XML comment using XDocument

Question

How to read xml comment when using XDocument?

XDocument doc = XDocument.Load("joker.xml");
 foreach (XElement element in doc.Descendants("server"))
            {
//I use this to read server tag...
}



<?xml version="1.0" encoding="ISO-8859-1"?>
<ho>
    <!-- For X use only -->
    <servers>
        <server NAME="xx" ></server>

    <!-- Dummy servers  -->
        <server NAME="xx" ></server>
        <server NAME="xx" ></server>
    </servers>
</ho>

Possible duplicate of [Reading XML comments in C#](http://stackoverflow.com/questions/6277966/reading-xml-comments-in-c-sharp) — rae1, Dec 09 '13 at 22:04
By "comment" you mean you want to read the "NAME" attribute ? I'm not seeing anything called "comment" in the XML structure provided. — Francis Ducharme, Dec 09 '13 at 22:31

BRAHIM Kamel · Accepted Answer · 2013-12-09T22:51:27.057

5

The Node object is the primary data type for the entire DOM.

A node can be an element node, an attribute node, a text node, or any other of the node types explained in the "Node types" chapter.

An XML element is everything from (including) the element's start tag to (including) the element's end tag.

     XDocument xdoc = XDocument.Load("");
       foreach (var node in xdoc.Descendants("servers").Nodes())
        {

            if (node is XComment)
            {
                //THEN  READ YOUR COMMENT 

            }

        }

edited Dec 09 '13 at 22:51

answered Dec 09 '13 at 22:10

BRAHIM Kamel

13,492
1
36
47

4

You shouldn't **ALWAYS** use nodes. In this case however you should. – Kevin Dec 09 '13 at 22:13
sorry I will update but in this case it's the best way to do it – BRAHIM Kamel Dec 09 '13 at 22:16
Would that return `server` comments? That's just dump of all comments in file – Sergey Berezovskiy Dec 09 '13 at 22:20
@Julie node will have the entire xml file. and when it check whether node is Xcomment it says it's not – John Ryann Dec 09 '13 at 22:29
@JohnRyann my code work but it's more tricky the code of lazyberezovsky – BRAHIM Kamel Dec 09 '13 at 22:32
@Julie, just curiosity , how would it work if it cant get pass the if node is XComment? – John Ryann Dec 09 '13 at 22:34
what you are looking for an XComment it will not pass the XComment I have Tried it before I posted it it'works well – BRAHIM Kamel Dec 09 '13 at 22:36
node has the entire XML file (joker.xml) and it doesnt pass if(node is XComment). it can not get inside the if statement – John Ryann Dec 09 '13 at 22:40

Sergey Berezovskiy · Answer 2 · 2013-12-09T22:30:24.717

4

Check node type when reading xml. If it's XComment then you are reading comment. E.g. in your case previous node of server element will be comment:

foreach(var s in doc.Descendants("server"))
{
    var comment = s.PreviousNode as XComment;
    if (comment != null)
        Console.WriteLine(comment.Value); // outputs "Dummy servers"
}

edited Dec 09 '13 at 22:30

answered Dec 09 '13 at 22:05

Sergey Berezovskiy

232,247
41
429
459

no descendans will return an xelement which is different from a node – BRAHIM Kamel Dec 09 '13 at 22:12
@JulieShannon take a look on OP code. He wants to take comments for servers. Servers are elements. – Sergey Berezovskiy Dec 09 '13 at 22:18
ok but doing like this you are filtering all elements did you understand the difference between node and element ? – BRAHIM Kamel Dec 09 '13 at 22:19
@JulieShannon looks like you don't understand how my code works – Sergey Berezovskiy Dec 09 '13 at 22:22
ok after you have updated your code now it's working I will upvote sorry I haven't see your update – BRAHIM Kamel Dec 09 '13 at 22:28

Ahmed ilyas · Answer 3 · 2013-12-09T22:10:56.923

0

you will have to use the XmlReader.Create method and read it and switch between the nodes to indicate which node it is current reading Dont be fooled by the Create method... it reads the xml file in question but creates an instance of the XmlReader object:

http://msdn.microsoft.com/en-us/library/system.xml.xmlreader.create(v=vs.110).aspx

XmlReader xmlRdr = XmlReader.Create("Joker.XML");
// Parse the file
while (xmlRdr.Read())
{
    switch (xmlRdr.NodeType)
    {
        case XmlNodeType.Element:
            // Current node is an Xml Element
            break;
        case XmlNodeType.Comment:
            // This is a comment so do something with xmlRdr.value

... and so on

PART 2 - for those who want to use LINQ (not that it makes a difference really)...

XDocument xml = XDocument.Load("joker.xml");
var commentNodes = from n in xml.Descendants("server")
                where n.NodeType == XmlNodeType.Comment
                select n;

foreach(XNode node in commentNodes)
{ 
  // now you are iterating over the comments it has found
}

edited Dec 09 '13 at 22:10

answered Dec 09 '13 at 22:03

Ahmed ilyas

5,722
8
44
72

1

no this is not an answer with Xdocument you have the support of Linq to xml he want a solution to his code not a new way to do it – BRAHIM Kamel Dec 09 '13 at 22:04
Sure but what difference does it make? LINQ just really makes it a little easier to read things. it doesnt change functionality. its another way of expressing things :). Furthermore the original question has not shown any usage on LINQ anyway. – Ahmed ilyas Dec 09 '13 at 22:05
A solution using XDocument is specifically asked for. – Kevin Dec 09 '13 at 22:17
@Kevin - thanks. I was giving other alternatives. But I understand your comment and stand corrected :) – Ahmed ilyas Dec 09 '13 at 22:18

c# Reading XML comment using XDocument

3 Answers3

Linked

Related