如何使用 XmlDocument 创建 XML 文档？

如何创建这样的 XML 文档？

<body>
<level1>
<level2>text</level2>
<level2>other text</level2>
</level1>
</body>

在 C # 中使用 XmlDocument

249117

小开

What about:

#region Using Statements
using System;
using System.Xml;
#endregion


class Program {
static void Main( string[ ] args ) {
XmlDocument doc = new XmlDocument( );


//(1) the xml declaration is recommended, but not mandatory
XmlDeclaration xmlDeclaration = doc.CreateXmlDeclaration( "1.0", "UTF-8", null );
XmlElement root = doc.DocumentElement;
doc.InsertBefore( xmlDeclaration, root );


//(2) string.Empty makes cleaner code
XmlElement element1 = doc.CreateElement( string.Empty, "body", string.Empty );
doc.AppendChild( element1 );


XmlElement element2 = doc.CreateElement( string.Empty, "level1", string.Empty );
element1.AppendChild( element2 );


XmlElement element3 = doc.CreateElement( string.Empty, "level2", string.Empty );
XmlText text1 = doc.CreateTextNode( "text" );
element3.AppendChild( text1 );
element2.AppendChild( element3 );


XmlElement element4 = doc.CreateElement( string.Empty, "level2", string.Empty );
XmlText text2 = doc.CreateTextNode( "other text" );
element4.AppendChild( text2 );
element2.AppendChild( element4 );


doc.Save( "D:\\document.xml" );
}
}

_{(1) Does a valid XML file require an xml declaration?}
_{(2) What is the difference between String.Empty and “” (empty string)?}

The result is:

<?xml version="1.0" encoding="UTF-8"?>
<body>
<level1>
<level2>text</level2>
<level2>other text</level2>
</level1>
</body>

But I recommend you to use LINQ to XML which is simpler and more readable like here:

#region Using Statements
using System;
using System.Xml.Linq;
#endregion


class Program {
static void Main( string[ ] args ) {
XDocument doc = new XDocument( new XElement( "body",
new XElement( "level1",
new XElement( "level2", "text" ),
new XElement( "level2", "other text" ) ) ) );
doc.Save( "D:\\document.xml" );
}
}

//a dictionary: Dictionary<string, string> Level2Data { {"level2", "text"}, {"level2", "other text"}, {"same_level2", "more text"} } //xml Decalration: XmlDocument xmlDoc = new XmlDocument(); XmlDeclaration xmlDeclaration = xmlDoc.CreateXmlDeclaration("1.0", "UTF-8", null); XmlElement root = xmlDoc.DocumentElement; xmlDoc.InsertBefore(xmlDeclaration, root); // add body XmlElement body = xmlDoc.CreateElement(string.Empty, "body", string.Empty); xmlDoc.AppendChild(body); XmlElement body = xmlDoc.CreateElement(string.Empty, "body", string.Empty); xmlDoc.DocumentElement.AppendChild(body); //without DocumentElement ->ERR foreach (KeyValuePair<string, string> entry in Level2Data) { //write to xml: - it works version 1. XmlNode keyNode = xmlDoc.CreateElement(entry.Key); //open TAB keyNode.InnerText = entry.Value; body.AppendChild(keyNode); //close TAB //Write to xmml verdion 2: (uncomment the next 4 lines and comment the above 3 - version 1 //XmlElement key = xmlDoc.CreateElement(string.Empty, entry.Key, string.Empty); //XmlText value = xmlDoc.CreateTextNode(entry.Value); //key.AppendChild(value); //body.AppendChild(key); }

Working with a dictionary ->level2 above comes from a dictionary in my case (just in case anybody will find it useful) Trying the first example I stumbled over this error: "This document already has a 'DocumentElement' node." I was inspired by the answer here

and edited my code: (xmlDoc.DocumentElement.AppendChild(body))

Both versions (1 and 2 inside foreach loop) give the output:

<?xml version="1.0" encoding="UTF-8"?>
<body>
<level1>
<level2>text</level2>
<level2>ther text</level2>
<same_level2>more text</same_level2>
</level1>
</body>

(Note: third line "same level2" in dictionary can be also level2 as the others but I wanted to ilustrate the advantage of the dictionary - in my case I needed level2 with different names.