Read and Write XML documents through xmldocument

Read and Write XML documents through xmldocument What is XML?
XML is short for the Extended Markup Language and a developed text format. For more information, see the W3 organization for http://www.w3.org/tr/1998/rec-xml-19980210. If you don't know about it, you will be out too much. How does. Net Process XML?
1. read and Write XML documents through xmldocument 2. use xmlreader to read XML, use xmlwriter to write xml3. use LINQ to XML to access xml4. use xmlscheme to define fixed-format XML documents. 5. XML serialization or deserialization Class 6. search for XML nodes using XPath 7. convert XML format using XSLT Read and Write XML documents through xmldocumentThere is the following XML :?

<?xml version="1.0" encoding="utf-8" ?> <students>   <! -- I am a text comment -->  <student name="Zhang Ping">     <courses>       <course name="Language? ">         <teacherComment>           <![CDATA[         Here is the comment of the Chinese teacher         ]]>        </teacherComment>           </course>         <course name="Mathematics">         <teacherComment>           <![CDATA[         Here is the comments from the math.         ]]>        </teacherComment>       </course>     </courses>   </student> </students>

1. How to Use xmldocument to read XML
I will use a piece of code to traverse all student and print all attributes of student and the value of the subnode?

/* Yukai blog Http://www.cnblogs.com/yukaizhao */using System; using System.Collections.Generic; using System.Text; using System.Xml;   namespace XmlExample {     class Program     {         static void Main(string[] args)         {             string xmlFilePath = @"X:\about.net\example\XmlExample\1.xml";             XmlDocument doc = new XmlDocument();             doc.Load(xmlFilePath);               // Use the XPath expression to select all student subnodes in the document             XmlNodeList studentNodeList = doc.SelectNodes("/students/student");             if (studentNodeList != null)             {                 foreach (XmlNode studentNode in studentNodeList)                 {                     // Get the attribute named name through attributes                     string name = studentNode.Attributes["name"].Value;                     Console.WriteLine("Student:" + name);                       // Obtain the courses subnode under the current node through the selectsinglenode Method                     XmlNode coursesNode = studentNode.SelectSingleNode("courses");                       // Obtain all level 1 subnodes of coursenode through the childnodes attribute                     XmlNodeList courseNodeList = coursesNode.ChildNodes;                     if (courseNodeList != null)                     {                         foreach (XmlNode courseNode in courseNodeList)                         {                             Console.Write("\t");                             Console.Write(courseNode.Attributes["name"].Value);                             Console.Write("Instructor comment");                             // You can obtain the first subnode of the course node through the firstnode attribute, and the lastnode can obtain the last subnode.                             XmlNode teacherCommentNode = courseNode.FirstChild;                             // Read the CDATA Node                             XmlCDataSection cdata = (XmlCDataSection)teacherCommentNode.FirstChild;                             Console.WriteLine(cdata.InnerText.Trim());                         }                     }                 }             }               Console.Write("\r\nPress any key to continue....");             Console.Read();         }     } }

Xmldocument itself is inherited from xmlnode. To read XML nodes, you can use firstchild, lastchild, nextsibling, and previussibling to read a single node, or read all child nodes through childnodes. You can also use the XPath expression selectnodes (string XPath) or selectsinglenode (string XPath) to read one or more qualified nodes. 2. How to edit XML through xmldocumentThis is also an example of reading XML in XML. We will use the CSHARP code to generate xml, as shown in the following code :?

/* Yukai blog Http://www.cnblogs.com/yukaizhao */using System; using System.Collections.Generic; using System.Text; using System.Xml;   namespace WriteXml {     class Program     {         static void Main(string[] args)         {             XmlDocument xmlDoc = new XmlDocument();             // Create the XML declaration section, that is, <? XML version = "1.0" encoding = "UTF-8"?>             xmlDoc.CreateXmlDeclaration("1.0", "utf-8", "yes");               // Create the root node             XmlNode rootNode = xmlDoc.CreateElement("students");               // Create a student subnode             XmlNode studentNode = xmlDoc.CreateElement("student");             // Create an attribute             XmlAttribute nameAttribute = xmlDoc.CreateAttribute("name");             nameAttribute .Value = "Classmate Zhang";             // XML node attachment attributes             studentNode.Attributes.Append(nameAttribute);                            // Create a courses subnode             XmlNode coursesNode = xmlDoc.CreateElement("courses");             XmlNode courseNode1 = xmlDoc.CreateElement("course");             XmlAttribute courseNameAttr = xmlDoc.CreateAttribute("name");             courseNameAttr.Value = "Language";             courseNode1.Attributes.Append(courseNameAttr);             XmlNode teacherCommentNode = xmlDoc.CreateElement("teacherComment");             // Create a CDATA Block             XmlCDataSection cdata = xmlDoc.CreateCDataSection("<Font color = \" Red \ "> This is a Chinese instructor's comment </font>");             teacherCommentNode.AppendChild(cdata);             courseNode1.AppendChild(teacherCommentNode);             coursesNode.AppendChild(courseNode1);             // Add a subnode             studentNode.AppendChild(coursesNode);               rootNode.AppendChild(studentNode);             // Add the root node             xmlDoc.AppendChild(rootNode);               // Save the XML document             xmlDoc.Save(@"d:\test.xml");               Console.WriteLine("Saved XML document");             }     } }

The main point of generating XML using xmldocument is to use createelement of the xmldocument instance to create an xmlnode or use the createattribute method to create an attribute, appendchild to attach an XML node, and appendattribute to the attribute set of the node through appendattribute.

Address: http://www.cnblogs.com/yukaizhao/archive/2011/07/19/csharp_xmldocument_access_xml.html