XmlTextReader

With XmlTextReader we parse XML data. This type acts upon a string containing XML markup. A while-loop is needed to keep reading from the object.

Type notes

We use the XmlTextReader constructor and develop a custom parser for XML data. This is an efficient approach to XML parsing.

Example program

A complete XML document is stored inside a string literal. With the StringReader constructor, we read this string as a StringReader.

using System;
using System.IO;
using System.Xml;

class Program
{
    static void Main()
    {
        string input = @"<?xml version=""1.0"" encoding=""utf-16""?><List>
    <Employee><ID>1</ID><First>David</First>
  <Last>Smith</Last><Salary>10000</Salary></Employee>
    <Employee><ID>3</ID><First>Mark</First>
  <Last>Drinkwater</Last><Salary>30000</Salary></Employee>
    <Employee><ID>4</ID><First>Norah</First>
  <Last>Miller</Last><Salary>20000</Salary></Employee>
    <Employee><ID>12</ID><First>Cecil</First>
  <Last>Walker</Last><Salary>120000</Salary></Employee>
    </List>";

        using (StringReader stringReader = new StringReader(input))
        using (XmlTextReader reader = new XmlTextReader(stringReader))
        {
            while (reader.Read())
            {
                if (reader.IsStartElement())
                {
                    switch (reader.Name)
                    {
                        case "Employee":
                            Console.WriteLine();
                            break;
                        case "ID":
                            Console.WriteLine("ID: " + reader.ReadString());
                            break;
                        case "First":
                            Console.WriteLine("First: " + reader.ReadString());
                            break;
                        case "Last":
                            Console.WriteLine("Last: " + reader.ReadString());
                            break;
                        case "Salary":
                            Console.WriteLine("Salary: " + reader.ReadString());
                            break;
                    }
                }
            }
        }
    }
}
ID: 1
First: David
Last: Smith
Salary: 10000

ID: 3
First: Mark
Last: Drinkwater
Salary: 30000

ID: 4
First: Norah
Last: Miller
Salary: 20000

ID: 12
First: Cecil
Last: Walker
Salary: 120000

XmlReader note

XmlReader and XmlTextReader are basically the same. When you call XmlTextReader.Create, an XmlReader is returned. The XmlTextReader type provides more constructors.

Summary

We looked at the XmlTextReader type. With XmlTextReader, we gain more constructors for using an XmlReader. These types can be used to develop fast parsers for XML files.