XML 增、删、改和查示例
1.已知有一个XML文件（bookstore.xml）如下：
<?xml version="1.0" encoding="gb2312"?>
<bookstore>
<book genre="fantasy" ISBN="2-3631-4">
<title>Oberon's Legacy</title>
<author>Corets, Eva</author>
<price>5.95</price>
</book>
</bookstore>
1、往<bookstore>节点中插入一个<book>节点：
XmlDocument xmlDoc=new XmlDocument();
xmlDoc.Load("bookstore.xml");
XmlNode root=xmlDoc.SelectSingleNode("bookstore");//查找<bookstore>
XmlElement xe1=xmlDoc.CreateElement("book");//创建一个<book>节点
xe1.SetAttribute("genre","李赞红");//设置该节点genre属性
xe1.SetAttribute("ISBN","2-3631-4");//设置该节点ISBN属性
XmlElement xesub1=xmlDoc.CreateElement("title");
xesub1.InnerText="CS从入门到精通";//设置文本节点
xe1.AppendChild(xesub1);//添加到<book>节点中
XmlElement xesub2=xmlDoc.CreateElement("author");
xesub2.InnerText="候捷";
xe1.AppendChild(xesub2);
XmlElement xesub3=xmlDoc.CreateElement("price");
xesub3.InnerText="58.3";
xe1.AppendChild(xesub3);
root.AppendChild(xe1);//添加到<bookstore>节点中
xmlDoc.Save("bookstore.xml");
//================
结果为：
<?xml version="1.0" encoding="gb2312"?>
<bookstore>
<book genre="fantasy" ISBN="2-3631-4">
<title>Oberon's Legacy</title>
<author>Corets, Eva</author>
<price>5.95</price>
</book>
<book genre="李赞红" ISBN="2-3631-4">
<title>CS从入门到精通</title>
<author>候捷</author>
<price>58.3</price>
</book>
</bookstore>
2、修改节点：将genre属性值为“李赞红“的节点的genre值改为“update李赞红”，将该节点的子节点<author>的文本修改为“亚胜”。
XmlNodeList nodeList=xmlDoc.SelectSingleNode("bookstore").ChildNodes;//获取bookstore节点的所有子节点
foreach(XmlNode xn in nodeList)//遍历所有子节点
{
XmlElement xe=(XmlElement)xn;//将子节点类型转换为XmlElement类型
if(xe.GetAttribute("genre")=="李赞红")//如果genre属性值为“李赞红”
{
xe.SetAttribute("genre","update李赞红");//则修改该属性为“update李赞红”
XmlNodeList nls=xe.ChildNodes;//继续获取xe子节点的所有子节点
foreach(XmlNode xn1 in nls)//遍历
{
XmlElement xe2=(XmlElement)xn1;//转换类型
if(xe2.Name=="author")//如果找到
{
xe2.InnerText="亚胜";//则修改
break;//找到退出来就可以了
}
}
break;
}
}
xmlDoc.Save("bookstore.xml");//保存。
//=================
最后结果为：
<?xml version="1.0" encoding="gb2312"?>
<bookstore>
<book genre="fantasy" ISBN="2-3631-4">
<title>Oberon's Legacy</title>
<author>Corets, Eva</author>
<price>5.95</price>
</book>
<book genre="update李赞红" ISBN="2-3631-4">
<title>CS从入门到精通</title>
<author>亚胜</author>
<price>58.3</price>
</book>
</bookstore>
3、删除 <book genre="fantasy" ISBN="2-3631-4">节点的genre属性，删除 <book genre="update李赞红" ISBN="2-3631-4">节点。
XmlNodeList xnl=xmlDoc.SelectSingleNode("bookstore").ChildNodes;
foreach(XmlNode xn in xnl)
{
XmlElement xe=(XmlElement)xn;
if(xe.GetAttribute("genre")=="fantasy")
{
xe.RemoveAttribute("genre");//删除genre属性
}
else if(xe.GetAttribute("genre")=="update李赞红")
{
xe.RemoveAll();//删除该节点的全部内容
}
}
xmlDoc.Save("bookstore.xml");
//====================
最后结果为：
<?xml version="1.0" encoding="gb2312"?>
<bookstore>
<book ISBN="2-3631-4">
<title>Oberon's Legacy</title>
<author>Corets, Eva</author>
<price>5.95</price>
</book>
<book>
</book>
</bookstore>
4、显示所有数据。
XmlNode xn=xmlDoc.SelectSingleNode("bookstore");
XmlNodeList xnl=xn.ChildNodes;
foreach(XmlNode xnf in xnl)
{
XmlElement xe=(XmlElement)xnf;
Console.WriteLine(xe.GetAttribute("genre"));//显示属性值
Console.WriteLine(xe.GetAttribute("ISBN"));
XmlNodeList xnf1=xe.ChildNodes;
foreach(XmlNode xn2 in xnf1)
{
Console.WriteLine(xn2.InnerText);//显示子节点点文本
}
}
留做参考,原文地址http://blog.yesky.com/75/richsee/1211075.shtml
2前台代码：html
<%
@ Page language="c#" Codebehind="Main.aspx.cs" AutoEventWireup="false" Inherits="DsAndXML.OpXMLFile.Main" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML> <HEAD> <title>Main</title> <meta name="GENERATOR" Content="Microsoft Visual Studio 7.0"> <meta name="CODE_LANGUAGE" Content="C#"> <meta name="vs_defaultClientScript" content="JavaScript"> <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5"> </HEAD> <body MS_POSITIONING="GridLayout"> <form id="Main" method="post" runat="server"> <FONT face="宋体"> <asp:DataGrid id="dgShow" style="Z-INDEX: 100; LEFT: 113px; POSITION: absolute; TOP: 32px" runat="server" Width="480px" Height="178px"></asp:DataGrid> <asp:Label id="Label3" style="Z-INDEX: 111; LEFT: 187px; POSITION: absolute; TOP: 383px" runat="server" Width="120px" Height="21px">新邮件地址：</asp:Label> <asp:Label id="Label2" style="Z-INDEX: 107; LEFT: 333px; POSITION: absolute; TOP: 274px" runat="server" Width="83px" Height="21px">邮件地址：</asp:Label> <asp:Button id="btnAdd" style="Z-INDEX: 104; LEFT: 298px; POSITION: absolute; TOP: 324px" runat="server" Text="添加"></asp:Button> <asp:Button id="btnDelete" style="Z-INDEX: 103; LEFT: 199px; POSITION: absolute; TOP: 324px" runat="server" Text="删除"></asp:Button> <asp:Button id="btnChange" style="Z-INDEX: 102; LEFT: 102px; POSITION: absolute; TOP: 382px" runat="server" Text="修改"></asp:Button> <asp:Button id="btnQuery" style="Z-INDEX: 101; LEFT: 101px; POSITION: absolute; TOP: 324px" runat="server" Text="查询"></asp:Button> <asp:DropDownList id="ddlName" style="Z-INDEX: 105; LEFT: 210px; POSITION: absolute; TOP: 274px" runat="server" Width="95px" Height="78px"></asp:DropDownList> <asp:Label id="Label1" style="Z-INDEX: 106; LEFT: 100px; POSITION: absolute; TOP: 274px" runat="server" Width="83px" Height="21px">姓名：</asp:Label> <asp:Label id="lbEmail" style="Z-INDEX: 109; LEFT: 459px; POSITION: absolute; TOP: 274px" runat="server" Width="231px"></asp:Label> <asp:TextBox id="tbNewMail" style="Z-INDEX: 110; LEFT: 330px; POSITION: absolute; TOP: 381px" runat="server" Width="208px" Height="26px"></asp:TextBox></FONT> </form> </body></HTML>XML文件dbGuest.xml<?xml version="1.0" standalone="yes"?><dbGuest> <User> <Name>aaa</Name> <City>shanghai</City> <Email>aaa@263.net</Email> <Message>ok</Message> <STime>2004-07-12T00:00:00.0000000+08:00</STime> </User> <User> <Name>shaoazhd</Name> <City>beijing</City> <Email>sss@22.net</Email> <Message>afsa</Message> <STime>2004-7-12 15:07:39</STime> </User> <User> <Name>Guset</Name> <City>上海</City> <Email>sfaf@22.net</Email> </User> <User> <Name>Guset</Name> <City>上海</City> <Email>ss@22.net</Email> </User></dbGuest>
using System;using System.Collections;using System.ComponentModel;using System.Data;using System.Drawing;using System.Web;using System.Web.SessionState;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.HtmlControls;using System.Xml;using System.Xml.XPath;namespace DsAndXML.OpXMLFile
{
/**//// <summary>
/// Main 的摘要说明。
/// </summary> public class Main : System.Web.UI.Page
{ protected System.Web.UI.WebControls.Button btnQuery;
protected System.Web.UI.WebControls.Button btnChange; protected System.Web.UI.WebControls.Button btnDelete; protected System.Web.UI.WebControls.Button btnAdd; protected System.Web.UI.WebControls.DropDownList ddlName; protected System.Web.UI.WebControls.Label Label1; protected System.Web.UI.WebControls.Label Label2; protected System.Web.UI.WebControls.Label lbEmail; protected System.Web.UI.WebControls.TextBox tbNewMail; protected System.Web.UI.WebControls.Label Label3; protected System.Web.UI.WebControls.DataGrid dgShow; private void Page_Load(object sender, System.EventArgs e) { // 在此处放置用户代码以初始化页面 if(!IsPostBack) Bind();
} private void Bind() { DataSet ds = new DataSet(); ds.ReadXml(Server.MapPath(".\\db\\dbGuest.xml")); dgShow.DataSource = ds.Tables[0].DefaultView; dgShow.DataBind(); XmlDocument doc = new XmlDocument(); doc.Load(Server.MapPath(".\\db\\dbGuest.xml")); XmlNodeList elemList = doc.GetElementsByTagName("Name"); ddlName.Items.Clear(); for(int i=0;i<elemList.Count;i++) ddlName.Items.Add(elemList[i].InnerXml); } Web Form Designer generated code#region Web Form Designer generated code override protected void OnInit(EventArgs e) { // // CODEGEN：该调用是 ASP.NET Web 窗体设计器所必需的。 // InitializeComponent(); base.OnInit(e); } /**//// <summary> /// 设计器支持所需的方法 - 不要使用代码编辑器修改 /// 此方法的内容。 /// </summary> private void InitializeComponent() { this.btnQuery.Click += new System.EventHandler(this.btnQuery_Click); this.btnChange.Click += new System.EventHandler(this.btnChange_Click); this.btnDelete.Click += new System.EventHandler(this.btnDelete_Click); this.btnAdd.Click += new System.EventHandler(this.btnAdd_Click); this.Load += new System.EventHandler(this.Page_Load); } #endregion private void btnQuery_Click(object sender, System.EventArgs e) { XmlDocument doc = new XmlDocument(); doc.Load(Server.MapPath(".\\db\\dbGuest.xml")); lbEmail.Text = doc.SelectSingleNode("//User[Name='"+ddlName.SelectedItem.Text+"']").ChildNodes.Item(2).InnerText; } private void btnChange_Click(object sender, System.EventArgs e) { XmlDocument xmlDoc = new XmlDocument(); xmlDoc.Load(Server.MapPath(".\\db\\dbGuest.xml")); XmlNodeList nodeList=xmlDoc.SelectSingleNode("dbGuest").ChildNodes;//获取dbGuest节点的所有子节点 foreach(XmlNode xn in nodeList)//遍历所有子节点 { XmlElement xe=(XmlElement)xn;//将子节点类型转换为XmlElement类型 XmlNodeList node = xe.GetElementsByTagName("Name"); if(node.Count>0) { if(node[0].InnerText==ddlName.SelectedItem.Text) { XmlNodeList nls=xe.ChildNodes;//继续获取xe子节点的所有子节点 foreach(XmlNode xn1 in nls)//遍历 { XmlElement xe2=(XmlElement)xn1;//转换类型 if(xe2.Name=="Email")//如果找到 { xe2.InnerText=tbNewMail.Text;//则修改 break;//找到退出来就可以了 } } break; } } } xmlDoc.Save(Server.MapPath(".\\db\\dbGuest.xml")); Bind(); } private void btnDelete_Click(object sender, System.EventArgs e) { XmlDocument xmlDoc = new XmlDocument(); xmlDoc.Load(Server.MapPath(".\\db\\dbGuest.xml")); XmlNodeList xnl=xmlDoc.SelectSingleNode("dbGuest").ChildNodes; foreach(XmlNode xn in xnl) { XmlElement xe=(XmlElement)xn; XmlNodeList node = xe.GetElementsByTagName("Name"); if(node.Count>0) { if(node[0].InnerText==ddlName.SelectedItem.Text) xe.RemoveAll();//删除该节点的全部内容 break; } } xmlDoc.Save(Server.MapPath(".\\db\\dbGuest.xml")); Bind(); } private void btnAdd_Click(object sender, System.EventArgs e) { XmlDocument xmlDoc = new XmlDocument(); xmlDoc.Load(Server.MapPath(".\\db\\dbGuest.xml")); XmlNode root=xmlDoc.SelectSingleNode("dbGuest");//查找<dbGuest> XmlElement xe1=xmlDoc.CreateElement("User");//创建一个<User>节点 XmlElement xesub1=xmlDoc.CreateElement("Name"); xesub1.InnerText="Guset";//设置文本节点 xe1.AppendChild(xesub1);//添加到<User>节点中 XmlElement xesub2=xmlDoc.CreateElement("City"); xesub2.InnerText="上海"; xe1.AppendChild(xesub2); XmlElement xesub3=xmlDoc.CreateElement("Email"); xesub3.InnerText="ss@22.net"; xe1.AppendChild(xesub3); root.AppendChild(xe1);//添加到<dbGuest>节点中 xmlDoc.Save(Server.MapPath(".\\db\\dbGuest.xml")); Bind(); } }
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