根据定制的 XML 文件进行随机抽取节

此类库中的两个类可以达成这一的一些效果：每次打开网页展现不同的标语、问候语，根据语录内容随机出题，随机显示新闻等等。当然XML格式的定制或者根据不同的XML文件适当修改类字段还是必要的。

using System;
using System.Xml;

namespace Quotations
{
    public class QuotationManager
    {
        private XmlDocument quoteDoc;
        private int quoteCount;

        public QuotationManager(string fileName)
        {
            quoteDoc = new XmlDocument();
            quoteDoc.Load(fileName);
            quoteCount = quoteDoc.DocumentElement.ChildNodes.Count;
        }

        public Quotation GetRandomQuote()
        {
            int i;
            Random x = new Random();
            i = x.Next(quoteCount - 1);
            return new Quotation(quoteDoc.DocumentElement.ChildNodes[i]);
        }
    }
}

using System;
using System.Xml;

namespace Quotations
{
    public class Quotation
    {
        public string Source { get; set; }
        public string Date { get; set; }
        public string QuotationText { get; set; }

        public Quotation(XmlNode quoteNode)
        {
            if (quoteNode.SelectSingleNode("source") != null)
            {
                Source = quoteNode.SelectSingleNode("source").InnerText;
            }

            if (quoteNode.SelectSingleNode("date")!=null)
            {
                Date = quoteNode.SelectSingleNode("date").InnerText;
            }

            QuotationText = quoteNode.FirstChild.InnerText;
        }
    }
}

这样调用：

string filePath = Server.MapPath("./quotations.xml");
Quotations.QuotationManager manager = new Quotations.QuotationManager(filePath);
Quotations.Quotation quotation = manager.GetRandomQuote();
Response.Write("<b>" + quotation.Source + "</b>(<i>" + quotation.Date + "</i>)");
Response.Write("<blockquote>" + quotation.QuotationText + "</blockquote>");