假定创建了XmlWriter的实例变量xmlWriter，下文中将使用此实例变量写Xml
1.如何使用XmlWriter写Xml文档声明
// WriteStartDocument方法可以接受一个bool参数（表示standalone，是否为独立文档）或者不指定参数standalone保持默认值
xmlWriter.WriteStartDocument(false|true);
注意在使用WriteStartDocument方法后最好调用xmlWrite.WriteEndDocument()方法来关闭所有可能未关闭标签
2.如何使用XmlWriter写xml节点以及属性
//写节点
xmlWriter.WriteStartElement("cat");
//给节点添加属性
xmlWriter.WriteAttributeString("color", "white");
//给节点内部添加文本
xmlWriter.WriteString("I'm a cat");
xmlWriter.WriteEndElement();
或者通过WriteElementString(string,string)方法写xml节点同时写下节点值，如下
//通过WriteElementString可以添加一个节点同时添加节点内容
xmlWriter.WriteElementString("pig", "pig is great");
3.如何写CData
xmlWriter.WriteStartElement("dog");
//写CData
xmlWriter.WriteCData("<strong>dog is dog</strong>");
xmlWriter.WriteEndElement();
4.如何使用XmlWriter添加注释
xmlWriter.WriteComment("this is an example writed by https://www.jb51.net ");
5.如何设置XmlWriter的输出格式，解决输出UTF-16问题
设置xml输出格式，需要通过XmlWriterSettings类，如下代码
XmlWriterSettings settings = new XmlWriterSettings();
//要求缩进
settings.Indent = true;
//注意如果不设置encoding默认将输出utf-16
//注意这儿不能直接用Encoding.UTF8如果用Encoding.UTF8将在输出文本的最前面添加4个字节的非xml内容
settings.Encoding = new UTF8Encoding(false);
//设置换行符
settings.NewLineChars = Environment.NewLine;
完整的代码示例如下：
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Xml;
namespace UseXmlWriter
{
class Program
{
static void Main(string[] args)
{
using (MemoryStream ms = new MemoryStream())
{
XmlWriterSettings settings = new XmlWriterSettings();
//要求缩进
settings.Indent = true;
//注意如果不设置encoding默认将输出utf-16
//注意这儿不能直接用Encoding.UTF8如果用Encoding.UTF8将在输出文本的最前面添加4个字节的非xml内容
settings.Encoding = new UTF8Encoding(false);
//设置换行符
settings.NewLineChars = Environment.NewLine;
using (XmlWriter xmlWriter = XmlWriter.Create(ms, settings))
{
//写xml文件开始<?xml version="1.0" encoding="utf-8" ?>
xmlWriter.WriteStartDocument(false);
//写根节点
xmlWriter.WriteStartElement("root");
//写字节点
xmlWriter.WriteStartElement("cat");
//给节点添加属性
xmlWriter.WriteAttributeString("color", "white");
//给节点内部添加文本
xmlWriter.WriteString("I'm a cat");
xmlWriter.WriteEndElement();
//通过WriteElementString可以添加一个节点同时添加节点内容
xmlWriter.WriteElementString("pig", "pig is great");
xmlWriter.WriteStartElement("dog");
//写CData
xmlWriter.WriteCData("<strong>dog is dog</strong>");
xmlWriter.WriteEndElement();
xmlWriter.WriteComment("this is an example writed by https://www.jb51.net ");
xmlWriter.WriteEndElement();
xmlWriter.WriteEndDocument();
}
//将xml内容输出到控制台中
string xml = Encoding.UTF8.GetString(ms.ToArray());
Console.WriteLine(xml);
}
Console.Read();
}
}
}
