Parse XML with C#

Question

I have this XML response that I get from ARIN:

<nets xmlns="http://www.arin.net/whoisrws/core/v1" xmlns:ns2="http://www.arin.net/whoisrws/rdns/v1" xmlns:ns3="http://www.arin.net/whoisrws/netref/v2" termsOfUse="https://www.arin.net/whois_tou.html">
    <limitExceeded limit="256">false</limitExceeded>
    <net termsOfUse="https://www.arin.net/whois_tou.html">
        <registrationDate>2003-05-09T16:14:30-04:00</registrationDate>
        <ref>http://whois.arin.net/rest/net/NET-216-113-160-0-1</ref>
        <ns2:delegations termsOfUse="https://www.arin.net/whois_tou.html">
            <ns2:delegationRef name="186.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/186.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="165.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/165.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="173.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/173.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="189.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/189.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="169.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/169.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="167.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/167.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="171.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/171.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="166.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/166.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="190.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/190.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="188.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/188.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="176.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/176.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="172.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/172.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="170.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/170.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="191.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/191.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="174.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/174.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="162.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/162.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="185.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/185.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="180.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/180.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="168.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/168.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="175.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/175.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="161.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/161.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="179.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/179.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="177.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/177.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="183.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/183.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="181.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/181.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="187.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/187.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="163.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/163.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="184.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/184.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="160.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/160.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="182.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/182.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="178.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/178.113.216.in-addr.arpa.</ns2:delegationRef>
            <ns2:delegationRef name="164.113.216.in-addr.arpa.">http://whois.arin.net/rest/rdns/164.113.216.in-addr.arpa.</ns2:delegationRef>
        </ns2:delegations>
        <endAddress>216.113.191.255</endAddress>
        <handle>NET-216-113-160-0-1</handle>
        <name>EBAY-QA-IT-1</name>
        <netBlocks>
            <netBlock>
                <cidrLength>19</cidrLength>
                <endAddress>216.113.191.255</endAddress>
                <description>Direct Assignment</description>
                <type>DS</type>
                <startAddress>216.113.160.0</startAddress>
            </netBlock>
        </netBlocks>
        <pocs termsOfUse="https://www.arin.net/whois_tou.html"/>
        <orgRef name="eBay, Inc" handle="EBAY">http://whois.arin.net/rest/org/EBAY</orgRef>
        <parentNetRef name="NET216" handle="NET-216-0-0-0-0">http://whois.arin.net/rest/net/NET-216-0-0-0-0</parentNetRef>
        <startAddress>216.113.160.0</startAddress>
        <updateDate>2012-03-02T08:03:18-05:00</updateDate>
        <version>4</version>
    </net>
</nets>

I am trying to get this information:

http://whois.arin.net/rest/org/EBAY

From this line:

<orgRef name="eBay, Inc" handle="EBAY">http://whois.arin.net/rest/org/EBAY</orgRef>

How can I get this information using C#?

I was trying to just parse the XML w/ XmlReader, but it seems like overkill. Maybe someone can help me determine what Regex rule I can use? — Sugitime, Oct 09 '12 at 22:39
@Sugitime Regex's aren't good for parsing XML. Why not just use Linq-To-XML or the XmlReader? That's what they're made for. — George Stocker, Oct 09 '12 at 22:41
@Sugitime, please don't try and use regex to parse XML, it makes it harder, not easier. See http://stackoverflow.com/a/1732454/383710 — DaveShaw, Oct 09 '12 at 22:41
XmlReader isn't that bad an idea in fact. The answers so far read the entire XML and store it into memory, which isn't really necessary here. Open the XML with an XMLReader and use [MoveToElement](http://msdn.microsoft.com/en-us/library/system.xml.xmlreader.movetoelement.aspx). Then you just have to get the attribute you need. — Laoujin, Oct 09 '12 at 22:43

score 7 · Accepted Answer · answered Oct 09 '12 at 22:39

7

Using Linq-Xml (available in .Net 3.5 and greater) you can do it using the following code snippet:

XNamespace xns = "http://www.arin.net/whoisrws/core/v1"; //The default xmlns from the root element.

var orgRefHandle =
  XDocument.Parse(xml)
  .Root
  .Element(xns + "net")
  .Element(xns + "orgRef")
  .Attribute("handle").Value;

answered Oct 09 '12 at 22:39

DaveShaw

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@Sugitime - Cool. You might want to check out http://LinqPad.net for an easy way test your Linq-Xml. – DaveShaw Oct 09 '12 at 22:49

CrazyCasta · Answer 2 · 2012-10-09T23:03:38.763

4

One way would be to use XmlDocument:

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.LoadXml(xmlString);

foreach(XmlElement ele in xmlDoc.DocumentElement.GetElementsByTagName("net"))
{
    // Writes value to console.
    Console.WriteLine(((XmlElement)ele.GetElementsByTagName("orgRef")).Attributes["handle"].Value);
}

edited Oct 09 '12 at 23:03

answered Oct 09 '12 at 22:40

CrazyCasta

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Yeah, I also wasn't sure if you might want the ability to handle multiple net elements. – CrazyCasta Oct 09 '12 at 23:03

score 0 · Answer 3 · edited Oct 09 '12 at 22:42

0

Load the content into an XmlDocument then you can use an XPath query to get a node's attribute using SelectSingleNode: /nets/limitexceeded/net/orgref/@Name and get the value.

edited Oct 09 '12 at 22:42

DaveShaw

52,123
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answered Oct 09 '12 at 22:40

Rob Hardy

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Parse XML with C#

3 Answers3