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;

namespace  MyXmlDemo
... {
    /**//// <summary>
    /// WebForm1 的摘要说明。
    /// </summary>
    public class WebForm1 : System.Web.UI.Page
    ...{
        protected System.Web.UI.WebControls.Label lbl;
        protected System.Web.UI.WebControls.Label lblOuter;
        protected System.Web.UI.WebControls.Button btnModify;
        protected System.Web.UI.WebControls.Button btnLoad;
    
        private void Page_Load(object sender, System.EventArgs e)
        ...{
            // 在此处放置用户代码以初始化页面
        }

        Web 窗体设计器生成的代码#region Web 窗体设计器生成的代码
        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.btnLoad.Click += new System.EventHandler(this.btnLoad_Click);
            this.btnModify.Click += new System.EventHandler(this.btnModify_Click);
            this.Load += new System.EventHandler(this.Page_Load);

        }
        #endregion

        private void btnLoad_Click(object sender, System.EventArgs e)
        ...{
            XmlDocument xmlDoc=new XmlDocument();
            xmlDoc.Load(Server.MapPath("test.xml"));
            //lbl.Text=Server.HtmlEncode(xmlDoc.InnerXml);

            XmlNode nodeX=xmlDoc.DocumentElement;
            lbl.Text=Server.HtmlEncode(nodeX.InnerXml);
            lblOuter.Text=Server.HtmlEncode(nodeX.OuterXml);

            foreach(XmlNode n in nodeX.ChildNodes[0].ChildNodes)
            ...{
                Response.Write(n.InnerText + "<br>");
            }
        }

        private void btnModify_Click(object sender, System.EventArgs e)
        ...{
            XmlDocument xmlDoc=new XmlDocument();
            xmlDoc.Load(Server.MapPath("test.xml"));

            XmlElement ele=xmlDoc.CreateElement("students");
            XmlAttribute attr=xmlDoc.CreateAttribute("id");
            attr.Value="1003";
            ele.Attributes.Append(attr);

            XmlElement eleName=xmlDoc.CreateElement("name");
            eleName.InnerText="tom";
            ele.AppendChild(eleName);

            
            XmlElement eleAge=xmlDoc.CreateElement("age");
            eleAge.InnerText="30";
            ele.AppendChild(eleAge);

            
            XmlElement eleGender=xmlDoc.CreateElement("gender");
            eleGender.InnerText="男";
            ele.AppendChild(eleGender);

            xmlDoc.DocumentElement.AppendChild(ele);
            xmlDoc.Save(Server.MapPath("test.xml"));
        }
    }
}

         private   void  btnOK_Click( object  sender, System.EventArgs e)
         ... {
            if(ddlCustomErrors.SelectedIndex==0) return;

            bool isExist=false;

            XmlDocument xmlDoc=new XmlDocument();
            xmlDoc.Load(Server.MapPath("Web.config"));

//            foreach(XmlNode n in xmlDoc.DocumentElement)
//            {
//                if(n.Name=="system.web")
//                {
//                    foreach(XmlNode nodX in n.ChildNodes)
//                    {
//                        if(nodX.Name=="customErrors")
//                        {
//                            nodX.Attributes[0].InnerText=ddlCustomErrors.SelectedItem.Value;
//                            isExist=true;
//                            break;
//                        }
//                    }
//                    if(!isExist)
//                    {
//                        XmlElement ele=xmlDoc.CreateElement("customErrors");
//                        XmlAttribute attr=xmlDoc.CreateAttribute("mode");
//                        attr.Value=ddlCustomErrors.SelectedItem.Value;
//                        ele.Attributes.Append(attr);
//                        n.AppendChild(ele);                    
//                    }
//                    break;    
//                }
//            }
            XmlNode nodeCustomerErrors=xmlDoc.SelectSingleNode("//customErrors");
            if(nodeCustomerErrors!=null)
            ...{
                nodeCustomerErrors.Attributes[0].InnerText=ddlCustomErrors.SelectedItem.Value;
            }
            else
            ...{
                nodeCustomerErrors=xmlDoc.CreateElement("customErrors");
                XmlAttribute attr=xmlDoc.CreateAttribute("mode");
                attr.Value=ddlCustomErrors.SelectedItem.Value;
                nodeCustomerErrors.Attributes.Append(attr);
                xmlDoc.SelectSingleNode("//system.web").AppendChild(nodeCustomerErrors);    
            }
            xmlDoc.Save(Server.MapPath("web.config"));
        }