随机选择具有相同名称的XML节点

Question

I have this XML file:

<Main>
<QA>
    <question>What is your favorite color?</question>
    <!--pick random!-->
    <answer>Blue</answer>
    <answer>Red</answer>
    <answer>Green</answer>
    <answer>Yellow</answer>
</QA>

<QA>
    <question>What is your favorite programming language?</question>
    <!--pick random!-->
    <answer>PHP</answer>
    <answer>C#</answer>
    <answer>Java</answer>
    <answer>VB.Net</answer>
</QA>

I want when the user enter one of the question that specified in above xml file, program pick a random answer from nodes. For example when user enters "What is your favorite programming language?" in TextBox, program must generate PHP,C#,Java or VB.Net randomly.

this is my code but not correct:

XmlDocument xml = new XmlDocument();
xml.Load("QA.xml");

XmlNodeList xList = xml.SelectNodes("Main/QA");
foreach (XmlNode xn in xList)
{
    string Question = xn["question"].InnerText;
    if (Question == txtQuestion.Text)
    {
        XmlNodeList answerlist = xml.SelectNodes("Main/QA/answer");
        foreach (XmlNode ans in answerlist)
        {
            Console.WriteLine(ans.InnerText);
        }
    }
}  

Output:

Blue Red Green Yellow PHP C# Java VB.Net

Please help.

Answer 1

using Linq To Xml,

Random rnd = new Random();
var xDoc = XDocument.Load("QA.xml");

var question = xDoc.Descendants("QA")
                   .First(d => d.Element("question").Value == txtQ.Text);

var answer = question.Elements()
                     .Skip(rnd.Next(0, question.Elements().Count()))
                     .First().Value;

Answer 2

Try this:

XmlDocument xml = new XmlDocument();
xml.Load("QA.xml");

XmlNodeList xList = xml.SelectNodes("Main/QA");
foreach (XmlNode xn in xList)
{
    string Question = xn["question"].InnerText;
    if (Question == txtQuestion.Text)
    {
        XmlNodeList answerlist = xn.SelectNodes("./answer");
        foreach (XmlNode ans in answerlist
            .Cast<XmlNode>()
            .OrderBy(elem => Guid.NewGuid()))
        {
            Console.WriteLine(ans.InnerText);
        }
    }
}