public class XmlControl
{
protected string strXmlFile;
protected XmlDocument objXmlDoc = new XmlDocument();

public XmlControl(string XmlFile)
{
//
// TODO: 在這裡加入建構函式的程式碼
//
try
{
objXmlDoc.Load(XmlFile);
}
catch (System.Exception ex)
{
throw ex;
}
strXmlFile = XmlFile;
}

public DataView GetData(string XmlPathNode)
{
//查找數據。返回一個DataView
DataSet ds = new DataSet();
StringReader read = new StringReader(objXmlDoc.SelectSingleNode(XmlPathNode).OuterXml);
ds.ReadXml(read);
return ds.Tables[0].DefaultView;
}

public void Replace(string XmlPathNode,string Content)
{
//更新節點內容。
objXmlDoc.SelectSingleNode(XmlPathNode).InnerText = Content;
}

public void Delete(string Node)
{
//刪除一個節點。
string mainNode = Node.Substring(0,Node.LastIndexOf("/"));
objXmlDoc.SelectSingleNode(mainNode).RemoveChild(objXmlDoc.SelectSingleNode(Node));
}

public void InsertNode(string MainNode,string ChildNode,string Element,string Content)
{
//插入一節點和此節點的一子節點。
XmlNode objRootNode = objXmlDoc.SelectSingleNode(MainNode);
XmlElement objChildNode = objXmlDoc.CreateElement(ChildNode);
objRootNode.AppendChild(objChildNode);
XmlElement objElement = objXmlDoc.CreateElement(Element);
objElement.InnerText = Content;
objChildNode.AppendChild(objElement);
}

public void InsertElement(string MainNode,string Element,string Attrib,string AttribContent,string Content)
{
//插入一個節點，帶一屬性。
XmlNode objNode = objXmlDoc.SelectSingleNode(MainNode);
XmlElement objElement = objXmlDoc.CreateElement(Element);
objElement.SetAttribute(Attrib,AttribContent);
objElement.InnerText = Content;
objNode.AppendChild(objElement);
}

public void InsertElement(string MainNode,string Element,string Content)
{
//插入一個節點，不帶屬性。
XmlNode objNode = objXmlDoc.SelectSingleNode(MainNode);
XmlElement objElement = objXmlDoc.CreateElement(Element);
objElement.InnerText = Content;
objNode.AppendChild(objElement);
}

public void Save()
{
//保存文檔。
try
{
objXmlDoc.Save(strXmlFile);
}
catch (System.Exception ex)
{
throw ex;
}
objXmlDoc = null;
}
}

=========================================================

实例应用：

string strXmlFile = Server.MapPath("TestXml.xml");
XmlControl xmlTool = new XmlControl(strXmlFile);

// 數據顯視
// dgList.DataSource = xmlTool.GetData("Book/Authors[ISBN=\"0002\"]");
// dgList.DataBind();

// 更新元素內容
// xmlTool.Replace("Book/Authors[ISBN=\"0002\"]/Content","ppppppp");
// xmlTool.Save();

// 添加一個新節點
// xmlTool.InsertNode("Book","Author","ISBN","0004");
// xmlTool.InsertElement("Book/Author[ISBN=\"0004\"]","Content","aaaaaaaaa");
// xmlTool.InsertElement("Book/Author[ISBN=\"0004\"]","Title","Sex","man","iiiiiiii");
// xmlTool.Save();

// 刪除一個指定節點的所有內容和屬性
// xmlTool.Delete("Book/Author[ISBN=\"0004\"]");
// xmlTool.Save();

// 刪除一個指定節點的子節點
// xmlTool.Delete("Book/Authors[ISBN=\"0003\"]");
// xmlTool.Save();