获取和设置 Web.config 或 XML 中的各个节点项和属性值

获取XML中的某个节点下所有子项的名称
 1        private void Page_Load(object sender, System.EventArgs e)
 2        {
 3            if(!Page.IsPostBack)
 4            {
 5                //打开某文件(假设WEB。CONFIG在根目录中)
 6                string filename="../web.config";
 7                XmlDocument  xmldoc= new XmlDocument();
 8                xmldoc.Load(filename);
 9
10                XmlNodeList topM=xmldoc.DocumentElement.ChildNodes;
11                foreach(XmlElement element in topM)
12                {
13                    if(element.Name.ToLower()=="appsettings")
14                    {
15                        XmlNodeList _node=element.ChildNodes;
16                        if ( _node.Count >0 )
17                        {
18                            DropDownList1.Items.Clear();
19                            foreach(XmlElement el in _node)
20                            {
21                                DropDownList1.Items.Add(el.Attributes["key"].InnerXml);
22                            }
23                        }
24                    }
25                }
26            }
27        }

设置XML中的各子项的属性值
 1        private void Button1_Click(object sender, System.EventArgs e)
 2        {
 3            string filename=Server.MapPath("/") + @"\web.config";
 4            XmlDocument  xmldoc= new XmlDocument();
 5            xmldoc.Load(filename);
 6
 7            XmlNodeList topM=xmldoc.DocumentElement.ChildNodes;
 8            foreach(XmlElement element in topM)
 9            {
10                if(element.Name.ToLower()=="appsettings")
11                {
12                    XmlNodeList _node=element.ChildNodes;
13                    if ( _node.Count >0 ) 
14                    {
15                        foreach(XmlElement el in _node)
16                        {
17                            if(el.Attributes["key"].InnerXml.ToLower()==this.DropDownList1.SelectedItem.Value.ToLower())
18                            {
19                                el.Attributes["value"].Value=this.TextBox1.Text;
20                            }
21                        }
22                    }
23                }
24            }
25            xmldoc.Save(filename);
26        }