My name
is
Jon Skeet

C# Unusual xml parsing

I have to parse one xml file to another, strictly defined one. The original file looks something like this:

<Data>
    <Client>
        <id>ID1</id>
        <Details>
            <detail1>1</detail1>
            <detail2>2</detail2>
        </Details>
        <Details>
            <detail1>3</detail1>
            <detail2>4</detail2>
        </Details>
    </Client>
    <Client>
        <id>ID2</id>
        <Details>
            <detail1>1</detail1>
            <detail2>2</detail2>
        </Details>
    </Client>
    <Client>
        <id>ID3</id>
        <Details>
            <detail1>1</detail1>
            <detail2>2</detail2>
        </Details>
    </Client>
</Data>

Basically all I need to do is to rewrite the file with different node names and parse some data within nodes, the structure itself remains the same.
Right now I have:

var ClientNodes = xml.SelectNodes("//Client");
for (int i = 0; i < ClientNodes.Count; i++)
{
    // this iterates through all Client nodes

    var DetailsNodes = xml.SelectNodes("//Details");
    for (int j = 0; j < DetailsNodes.Count; j++)
    {
        // this iterates through ALL "//Details" nodes and that's the problem

    }

}

If I just loop through the Details node as seen above, I would recieve something like:

<Client>
    <id>ID1</id>
    <Details>
        <detail1>1</detail1>
        <detail2>2</detail2>
    </Details>
    <Details>
        <detail1>3</detail1>
        <detail2>4</detail2>
    </Details>
    <Details>
        <detail1>1</detail1>
        <detail2>2</detail2>
    </Details>
    <Details>
        <detail1>1</detail1>
        <detail2>2</detail2>
    </Details>

I have no clue how to approach this problem. The main issue is that some Client nodes can have 2 or more Details nodes.

The best solution (I think) would be finding a way to iterate through all nodes within a single Client node, but I have not idea if that's possible (and that's why I decided to write my problem here), plus the files I have to deal with have ~20 nodes within a single Details node.

I would strongly recommend using LINQ to XML instead of XPath for this. (You can use XPath, certainly - but it's less readable IMO. You'd just need to use ClientNodes[i].SelectNodes("Details").)

var xml = XDocument.Load(...);
foreach (var client in xml.Root.Elements("Client"))
{
    // Do whatever you need to here
    foreach (var detail in client.Elements("Details"))
    {
        // Do whatever you need to here
    }
}

LINQ to XML is a wonderful XML API, and well worth learning about...

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