C#：XML操作总结2 包括读取、插入、修改、删除
1、读取节点中某一个属性的值
/// <summary>
/// 读取节点中某一个属性的值。如果attribute为空，则返回整个节点的InnerText，否则返回具体attribute的值
/// </summary>
/// <param name="path">xml文件路径</param>
/// <param name="node">节点</param>
/// <param name="attribute">节点中的属性</param>
/// <returns>如果attribute为空，则返回整个节点的InnerText，否则返回具体attribute的值</returns>
/// 使用实例: XMLHelper.Read(path, "PersonF/person[@Name='Person2']", "");
/// XMLHelper.Read(path, "PersonF/person[@Name='Person2']", "Name");
public static string Read(string path, string node, string attribute)
{
string value = "";
try
{
XmlDocument doc = new XmlDocument();
doc.Load(path);
XmlNode xn = doc.SelectSingleNode(node);
value = (attribute.Equals("") ? xn.InnerText : xn.Attributes[attribute].Value);
}
catch(Exception e)
{
Console.WriteLine(e.Message);
}
return value;
}
2、 向节点中增加节点元素，属性
/// <summary>
/// 向节点中增加节点元素，属性
/// </summary>
/// <param name="path">路径</param>
/// <param name="node">要操作的节点</param>
/// <param name="element">要增加的节点元素，可空可不空。非空时插入新的元素，否则插入该元素的属性</param>
/// <param name="attribute">要增加的节点属性，可空可不空。非空时插入元素值，否则插入元素值</param>
/// <param name="value">要增加的节点值</param>
/// 使用实例：XMLHelper.Insert(path, "PersonF/person[@Name='Person2']","Num", "ID", "88");
/// XMLHelper.Insert(path, "PersonF/person[@Name='Person2']","Num", "", "88");
/// XMLHelper.Insert(path, "PersonF/person[@Name='Person2']", "", "ID", "88");
public static void Insert(string path, string node, string element, string attribute, string value)
{
try
{
XmlDocument doc = new XmlDocument();
doc.Load(path);
XmlNode xn = doc.SelectSingleNode(node);
//如果element，则增加该属性
if (string.IsNullOrEmpty(element))
{
//如果attribute不为空，增加该属性
if (!string.IsNullOrEmpty(attribute))
{
XmlElement xe = (XmlElement)xn;
// <person Name="Person2" ID="88"> XMLHelper.Insert(path, "PersonF/person[@Name='Person2']","Num", "ID", "88");
xe.SetAttribute(attribute, value);
}
}
else //如果element不为空，则preson下增加节点
{
XmlElement xe = doc.CreateElement(element);
if (string.IsNullOrEmpty(attribute))
// <person><Num>88</Num></person> XMLHelper.Insert(path, "PersonF/person[@Name='Person2']","Num", "", "88");
xe.InnerText = value;
else
// <person> <Num ID="88" /></person> XMLHelper.Insert(path, "PersonF/person[@Name='Person2']", "", "ID", "88");
xe.SetAttribute(attribute, value);
xn.AppendChild(xe);
}
doc.Save(path);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
3、修改节点值
/// <summary>
/// 修改节点值
/// </summary>
/// <param name="path">路径</param>
/// <param name="node">要修改的节点</param>
/// <param name="attribute">属性名，非空时修改节点的属性值，否则修改节点值</param>
/// <param name="value">属性值</param>
/// 实例 XMLHelper.Update(path, "PersonF/person[@Name='Person3']/ID", "", "888");
/// XMLHelper.Update(path, "PersonF/person[@Name='Person3']/ID", "Num", "999");
public static void Update(string path, string node, string attribute, string value)
{
try
{
XmlDocument doc = new XmlDocument();
doc.Load(path);
XmlNode xn = doc.SelectSingleNode(node);
XmlElement xe = (XmlElement)xn;
if (string.IsNullOrEmpty(attribute))
xe.InnerText = value;//原<ID>2</ID> 改变:<ID>888</ID> XMLHelper.Update(path, "PersonF/person[@Name='Person3']/ID", "", "888");
else
xe.SetAttribute(attribute, value); //原<ID Num="3">888</ID> 改变<ID Num="999">888</ID> XMLHelper.Update(path, "PersonF/person[@Name='Person3']/ID", "Num", "999");
doc.Save(path);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
4、删除数据
/// <summary>
/// 删除数据
/// </summary>
/// <param name="path">路径</param>
/// <param name="node">要删除的节点</param>
/// <param name="attribute">属性，为空则删除整个节点，不为空则删除节点中的属性</param>
/// 实例：XMLHelper.Delete(path, "PersonF/person[@Name='Person3']/ID", "");
/// XMLHelper.Delete(path, "PersonF/person[@Name='Person3']/ID", "Num");
public static void Delete(string path, string node, string attribute)
{
try
{
XmlDocument doc = new XmlDocument();
doc.Load(path);
XmlNode xn = doc.SelectSingleNode(node);
XmlElement xe = (XmlElement)xn;
if (string.IsNullOrEmpty(attribute))
xn.ParentNode.RemoveChild(xn);// <ID Num="999">888</ID>的整个节点将被移除 XMLHelper.Delete(path, "PersonF/person[@Name='Person3']/ID", "");
else
xe.RemoveAttribute(attribute);//<ID Num="999">888</ID> 变为<ID>888</ID> XMLHelper.Delete(path, "PersonF/person[@Name='Person3']/ID", "Num");
doc.Save(path);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
5、调用方法
public static void XMLMTest()
{
string path = "http://www.cnblogs.com/../Person.xml";
XMLHelper.Read(path, "PersonF/person[@Name='Person2']", "Name");
XMLHelper.Insert(path, "PersonF/person[@Name='Person2']", "Num", "ID", "88");
XMLHelper.Insert(path, "PersonF/person[@Name='Person2']", "Num", "", "88");
XMLHelper.Insert(path, "PersonF/person[@Name='Person2']", "", "ID", "88");
XMLHelper.Update(path, "PersonF/person[@Name='Person3']", "Num", "888");
XMLHelper.Update(path, "PersonF/person[@Name='Person3']/ID", "Num", "999");
XMLHelper.Update(path, "PersonF/person[@Name='Person3']/ID", "", "888");
XMLHelper.Delete(path, "PersonF/person[@Name='Person3']/ID", "Num");
XMLHelper.Delete(path, "PersonF/person[@Name='Person3']/ID", "");
}
6、XML文件
<?xml version="1.0" encoding="utf-8"?>
<PersonF xmlns="" Name="work hard work smart!">
<person Name="Person1">
<ID>1</ID>
<Name>XiaoA</Name>
<Age>59</Age>
</person>
<person Name="Person2" ID="88">
<ID>2</ID>
<Name>XiaoB</Name>
<Age>29</Age>
<Num ID="88" />
<Num>88</Num>
</person>
<person Name="Person3">
<ID Num="999">888</ID>
<Name>XiaoC</Name>
<Age>103</Age>
</person>
<person Name="Person4">
<ID>4</ID>
<Name>XiaoD</Name>
<Age>59</Age>
</person>
<person Name="Person5">
<Name>work hard work smart!</Name>
<ID>32</ID>
</person>
<person Name="Person5">
<Name>work hard work smart!</Name>
<ID>32</ID>
</person>
</PersonF>
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