Question

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

Answer 1

怎么样：

#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)?}

结果是：

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

但我建议您使用LINQ to XML，这样更简单，更易读：

#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" );
    }
}

Answer 2

使用字典->在我的情况下，上面的level2来自字典（以防万一有人发现它有用）尝试第一个示例时，我偶然发现了此错误： “此文档已具有'DocumentElement'节点。” 我的答案是here

并编辑了我的代码：（xmlDoc。 DocumentElement .AppendChild（body））

//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);
}

两个版本（foreach循环中的1和2）都给出输出：

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

（注意：字典中的第三行“与level2相同”也可以与其他级别相同，但是我想展示字典的优势-在我的情况下，我需要使用不同名称的level2。

如何使用XmlDocument创建XML文档？

2 个答案: