学步园

该类适应读写如下格式的.xml,.config文档
<?xml version="1.0" encoding="utf-8" standalone="no"?>
<!--This is a config file ,writer by furenjun-->
<configuration>
  <appSettings>
    <add key="SqlStr0" value="0" />
    <add key="SqlStr1" value="1" />
    <add key="2006-7-3 16:05:08" value="1" />
  </appSettings>
</configuration>

using System;
using System.Configuration ;
using System.Reflection ;
using System.Xml;
using System.IO;
using System.Collections.Specialized;
using System.Collections;
using System.Data ;
using System.Diagnostics;
using System.Windows.Forms;
namespace 读写配置文件
{
    /**//// <summary>
    /// MrfuRWXmlFile 的摘要说明。
    /// </summary>
    public class MrfuRWXmlFile
    {
        public static string ConfigFullName="";
    
        
        private NameValueCollection appSettings = null;
        public MrfuRWXmlFile()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
            //            Assembly MyAssembly= Assembly.GetExecutingAssembly();
            //            string ConfigLocPath=MyAssembly.Location;
            //            string strDireName=Path.GetDirectoryName(ConfigLocPath) ;
            //            //MessageBox.Show(ConfigLocPath+"\n"+strDireName) ;
            //            ConfigFullName=ConfigLocPath+".config";
            ConfigFullName=Application.StartupPath+@"\myProject.config" ;
            
            //MessageBox.Show(ConfigFullName) ;
        }
        private static void CreateNewXmlFile()
        {
            XmlTextWriter myXmlTextWriter = new XmlTextWriter (ConfigFullName, System.Text.Encoding.UTF8 );
            myXmlTextWriter.Formatting = Formatting.Indented;
            myXmlTextWriter.WriteStartDocument(false); //设置standalone="no"   //当为（true）时 <?xml version="1.0" standalone="yes" ?> 
            //    myXmlTextWriter.WriteDocType("bookstore", null, "books.dtd", null);
            myXmlTextWriter.WriteComment("This is a config file ,writer by furenjun");
            myXmlTextWriter.WriteStartElement("configuration");
            myXmlTextWriter.WriteStartElement("appSettings", null);
            '写入其它元素'#region '写入其它元素'
            //            myXmlTextWriter.WriteAttributeString("genre","autobiography");
            //            myXmlTextWriter.WriteAttributeString("publicationdate","1979");
            //            myXmlTextWriter.WriteAttributeString("ISBN","0-7356-0562-9");
            //            myXmlTextWriter.WriteElementString("title", null, "The Autobiography of Mark Twain");
            //            myXmlTextWriter.WriteStartElement("Author", null);
            //            myXmlTextWriter.WriteElementString("first-name", "Mark");
            //            myXmlTextWriter.WriteElementString("last-name", "Twain");
            //            myXmlTextWriter.WriteEndElement();
            //            myXmlTextWriter.WriteElementString("price", "7.99");
            #endregion
            myXmlTextWriter.WriteEndElement();
            myXmlTextWriter.WriteEndElement();

            //Write the XML to file and close the myXmlTextWriter
            myXmlTextWriter.Flush();
            myXmlTextWriter.Close();
        }
        public MrfuRWXmlFile(string ConfigFilePath)
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
    
            ConfigFullName=ConfigFilePath;
            
        }

        public string GsConfigFilePath
        {
            get{return ConfigFullName;}
            set{ConfigFullName=value;}
        }

        //初始化xml文档
        //首先请右击"项目"-->添加一个新项-->选择"应用程序配置文件"-->点击确定
        public static bool CreateXmlFile()
        {
            if(!File.Exists(ConfigFullName) )
                CreateNewXmlFile();

            bool bflag=true;
            ConfigXmlDocument configXmlDoc=new ConfigXmlDocument();//  XmlDocument();
            configXmlDoc.Load(ConfigFullName) ;
            //检查结点是否存在#region //检查结点是否存在
            //            //XmlNodeList xList=configXmlDoc.SelectNodes ("//appSettings");//可以根据实际需要更改它的查找范围.如SelectNodes("//User")
            //            XmlNodeList xList=configXmlDoc.DocumentElement.ChildNodes  ;
            //            
            //
            //            if (xList.Count> 0)
            //            {
            //                
            //            
            //                foreach(XmlNode node in xList)
            //                {
            //                    if(node.Name =="appSettings")
            //                        MessageBox.Show ("找到");
            //                    return;
            //                }
            //            }
            //            else
            //            {
            //                MessageBox.Show("no nodes") ;
            //            }
            //
            //            XmlNode root2 = configXmlDoc.FirstChild;
            //
            //            //Display the contents of the child nodes.
            //            if (root2.HasChildNodes)
            //            {
            //                string strs="";
            //                for (int i=0; i<root2.ChildNodes.Count; i++)
            //                {
            //                    strs+=(root2.ChildNodes[i].InnerText)+"\n";
            //                }
            //                MessageBox.Show(strs) ;
            //            }

            #endregion
            XmlNode appSettingsNode;
            appSettingsNode = configXmlDoc.SelectSingleNode("configuration/appSettings");
            
            if(appSettingsNode.LocalName=="appSettings")  //或者(appSettingNode!=null)
            {
                //如果xml文档中已存在该结点则采用选择定位该结点的方法
                appSettingsNode.RemoveAll();
                //MessageBox.Show(appSettingsNode.LocalName) ;
            }
            else
            {
                // Create a new element node.
                XmlNode newElem;
                newElem = configXmlDoc.CreateNode(XmlNodeType.Element, "appSettings", "");  
                //newElem.InnerText = "290";
                //"Add the new element to the document"
                XmlElement root = configXmlDoc.DocumentElement;
                root.AppendChild(newElem);
                //("Display the modified XML document");
                //Console.WriteLine(configXmlDoc.OuterXml);
                appSettingsNode =newElem;
            }
            try
            {        
                for (int i = 0; i < 2; i++)
                {
                    string key = "SqlStr"+i.ToString() ;
                    string val = i.ToString() ;
                    
                    //创建结点
                    XmlNode node = configXmlDoc.CreateNode(XmlNodeType.Element, "add", "");

                    //创建属性"key"并为其赋值
                    XmlAttribute attr = configXmlDoc.CreateAttribute("key");
                    attr.Value = key;
                    node.Attributes.Append(attr);
                    //创建属性"value"并为其赋值
                    attr = configXmlDoc.CreateAttribute("value");
                    attr.Value = val;
                    node.Attributes.Append(attr);
                    appSettingsNode.AppendChild(node);

                }
                configXmlDoc.Save(ConfigFullName);
                
                //MessageBox.Show("创建Xml文档结点成功.","系统提示",MessageBoxButtons.OK ,MessageBoxIcon.Information ) ;
            }
            catch (Exception ex)
            {
                bflag=false;
                throw new ConfigurationException(ex.ToString() );
            }
            return bflag;
        }
        
        private void LoadFromFile()
        {
            //if (appSettings == null)
            //{
            try
            {
                //string filePath=@"E:\淄博市鲁中机动车检测中心数据联网软件\FromHlk\读写配置文件\ConfigurationSettingsRW_demo\ConfigurationSettingsRW_demo\ConfigurationSettingsRW.exe.config";
                ConfigXmlDocument configXml = new ConfigXmlDocument();//  XmlDocument();
                //configXml.Load(filePath);//this.configFilePath);
                configXml.Load(ConfigFullName);
                //MessageBox.Show(ConfigFullName ) ;
                XmlNode appSettingsNode = configXml.SelectSingleNode("configuration/appSettings");
                //MessageBox.Show(appSettingsNode.LocalName) ;
                if(appSettingsNode.LocalName=="appSettings")
                {
                    NameValueSectionHandler handler = new NameValueSectionHandler();
                    
                    
                    appSettings = new NameValueCollection((NameValueCollection)handler.Create(null, null, appSettingsNode));
                }
                
            }
            catch (Exception ex)
            {
                throw new ConfigurationException("Error while loading appSettings. Message: " + ex.Message, ex);
            }
            //}
        }


        /**//// <summary>
        /// 获取配置文件中的结点"appSettings"中的值
        /// </summary>
        /// <returns></returns>
        public DataTable GetSettingsValue()
        {
            LoadFromFile();
            DataTable tblAppSettings=new DataTable("Settings") ;
            tblAppSettings.Columns.Add("key", typeof(System.String));
            tblAppSettings.Columns.Add("valu