Add childnode to xml doc

Question

I am trying to search a XML file and if a certain dependency is not found, add that dependency to the end of the <dependencies>. My XML File looks like this:

    <config>
      <settings>
      ...
      </settings>
<dependencies>
<dependency key="#0" type="Windows" name="Microsoft Windows XP" namepart="false"/>
    .
    .
    .
<dependancy key="#4" type="Windows" name="Microsoft Windows 7" namepart="false" />
</dependencies>

Now I would like to add a 5th dependency via code. (<dependancy key="#5" type="Windows" name="Microsoft Windows NT" namepart="false" />) How would I go about doing that. I have tried using XMLElement and appending it to the end.

Answer 1

Xml Document is not orderd. you can check for particular node , usualy using a key attribute.

    XmlDocument doc=new XmlDocument();
    doc.LoadXMl(youxmlstring);
    XmlNode node=doc.SelectSingleNode("//dependancy/@name='Microsoft Windows NT'");
    if (node==null)
    {
            //no such node
            //insert new node
    }

To calculate new key attribute value you could use something like this

    //assuming key is currectly ordered
    int nextKey=doc.SelectNodes("//dependancy").Count;      

see

http://www.codeproject.com/Articles/9494/Manipulate-XML-data-with-XPath-and-XmlDocument-C