XML文件的读取

读取XML也有两种方式，如果要读取一个大且复杂的XML文件，使用XmlDocument会比较慢，使用XmlTextReader就会比较快

1. 使用XmlDocument读取XML

class Program
{
    const string sourceXml =
     “<Book PublishYear=\“2009\”>” +
     “<Title>Programming, art or engineering?</Title>” + 
     “<Author>Billy Bob</Author>” + 
     “</Book>”;

    static void Main(string[] args)
    {
        XmlDocument doc = new XmlDocument();
        doc.LoadXml(sourceXml);
        Console.WriteLine(“Publish Year: {0}”, doc.GetElementsByTagName(“Book”)[0].Attributes[“PublishYear”].Value);
        Console.WriteLine(“Author: {0}”, doc.GetElementsByTagName(“Author”)[0].InnerText);
    }
}

2. 使用XmlTextReader读取XML

XmlTextReade类能从很多种源中读取Xml。但需要使用StringReader为XmlTextReader将一个字符串转换成流

class Program
{
    const string sourceXml =
“<Book PublishYear=\”2009\”>” +
“<Title>Programming, art or engineering?</Title>” +
“<Author>Billy Bob</Author>” +
“</Book>”;

    static void Main(string[] args)
    {
        string publishYear = null, author = null;
        using (StringReader reader = new StringReader(sourceXml))
        using (XmlTextReader xmlReader = new XmlTextReader(reader))
        {
            while (xmlReader.Read())
            {
                if (xmlReader.NodeType == XmlNodeType.Element)
                {
                    if (xmlReader.Name == “Book”)
                    {
                        if (xmlReader.MoveToAttribute(“PublishYear”))
                        {
                            publishYear = xmlReader.Value;
                        }
                    }
                    else if (xmlReader.Name == “Author”)
                    {
                        xmlReader.Read();
                        author = xmlReader.Value;
                    }
                }
            }
        }

        Console.WriteLine(“Publish Year: {0}”, publishYear);
        Console.WriteLine(“Author: {0}”, author);
    }
}