<?xml version="1.0" encoding="utf-8"?>

<configuration>

  <appSettings>

    <add key="ConnectionString" value="server=192.168.100.116;database=BDCY;uid=sa;pwd=123456;" />

    <add key="ConnString" value="server=(local);database=gxjd;uid=sa;pwd=" />

    <add key="BakData" value="W1" />

    <add key="dogServer" value="192.168.100.116">

    </add>

    <add key="dogport" value="">

    </add>

  </appSettings>

</configuration>

   /// <summary>

        /// 读取XML中的数据数据库连接字符串

        /// </summary>

        /// <param name="value"></param>

        /// <param name="key"></param>

        /// <returns></returns>

        private string ConfigGetValues(string key)

        {

            string strRes = string.Empty;

            XmlDocument xDoc = new XmlDocument();

            xDoc.Load("Config.xml");

            XmlNode xNode;

            XmlElement xElement;

            xNode = xDoc.SelectSingleNode("//appSettings");

            xElement = (XmlElement)xNode.SelectSingleNode("add[@key='"+key+"']");

            if (xElement != null)

            {

                strRes = xElement.GetAttribute("value");

            }

            return strRes;

        }

  /// <summary>

        /// 写入XML中的数据

        /// </summary>

        /// <param name="key">键</param>

        /// <param name="value">值</param>

        /// <returns></returns>

        private void ConfigSetValues(string key,string value)

        {

            XmlDocument xDoc = new XmlDocument();

            xDoc.Load("Config.xml");

            XmlNode xNode;

            XmlElement xElement;

            XmlElement xElement1;

            xNode = xDoc.SelectSingleNode("//appSettings");

            xElement = (XmlElement)xNode.SelectSingleNode("//add[@key='"+key+"']");

            if (xElement != null)

            {

                xElement.SetAttribute("value", value); //"value"固定的AppStrings结点属性

            }

            else

            {

                xElement1 = xDoc.CreateElement("add");

                xElement1.SetAttribute("key", key);      //"key"固定的AppStrings结点属性

                xElement1.SetAttribute("value", value);  //"value"固定的AppStrings结点属性

                xNode.AppendChild(xElement1);

            }

            xDoc.Save("Config.xml");

        }

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Xml;

namespace Config

{

    public partial class XMLCheck : Form

    {

        public XMLCheck()

        {

            InitializeComponent();

        }

        //读取数据

        private void btnRead_Click(object sender, EventArgs e)

        {

            GetConfigSub("ConnectionString");

        }

        //写入数据

        private void btnWrite_Click(object sender, EventArgs e)

        {

            SetConfigSub();

            MessageBox.Show("修改成功！");

        }

        /// <summary>

        /// 读取XML中的数据数据库连接字符串

        /// </summary>

        /// <param name="value"></param>

        /// <param name="key"></param>

        /// <returns></returns>

        private string ConfigGetValues(string key)

        {

            string strRes = string.Empty;

            XmlDocument xDoc = new XmlDocument();

            xDoc.Load("Config.xml");

            XmlNode xNode;

            XmlElement xElement;

            xNode = xDoc.SelectSingleNode("//appSettings");

            xElement = (XmlElement)xNode.SelectSingleNode("add[@key='"+key+"']");

            if (xElement != null)

            {

                strRes = xElement.GetAttribute("value");

            }

            return strRes;

        }

        /// <summary>

        /// 获取数据库连接的子信息

        /// </summary>

        private void GetConfigSub(string key)

        {

            string strRes = ConfigGetValues(key);

            string[] arr = strRes.Split(';');

            txbServerName.Text =arr[].Substring(arr[].IndexOf('=')+);

            txbDBName.Text = arr[].Substring(arr[].IndexOf('=') + );

            txbAccountName.Text = arr[].Substring(arr[].IndexOf('=') + );

            txbDBPwd.Text = arr[].Substring(arr[].IndexOf('=') + );

            txbDogAddress.Text = ConfigGetValues("dogServer");

        }

        /// <summary>

        /// 写入XML中的数据

        /// </summary>

        /// <param name="key">键</param>

        /// <param name="value">值</param>

        /// <returns></returns>

        private void ConfigSetValues(string key,string value)

        {

            XmlDocument xDoc = new XmlDocument();

            xDoc.Load("Config.xml");

            XmlNode xNode;

            XmlElement xElement;

            XmlElement xElement1;

            xNode = xDoc.SelectSingleNode("//appSettings");

            xElement = (XmlElement)xNode.SelectSingleNode("//add[@key='"+key+"']");

            if (xElement != null)

            {

                xElement.SetAttribute("value", value); //"value"固定的AppStrings结点属性

            }

            else

            {

                xElement1 = xDoc.CreateElement("add");

                xElement1.SetAttribute("key", key);      //"key"固定的AppStrings结点属性

                xElement1.SetAttribute("value", value);  //"value"固定的AppStrings结点属性

                xNode.AppendChild(xElement1);

            }

            xDoc.Save("Config.xml");

        }

        /// <summary>

        /// 设置数据库连接字符串

        /// </summary>

        private void SetConfigSub()

        {

            string serverName = "server=" + txbServerName.Text + ";";

            string dbName = "database=" + txbDBName.Text + ";";

            string dbAccount = "uid=" + txbAccountName.Text + ";";

            string dbPwd = "pwd=" + txbDBPwd.Text + ";";

            string dogServer = txbDogAddress.Text;

            string appSetting = serverName + dbName + dbAccount + dbPwd;

            ConfigSetValues("ConnectionString", appSetting);

            ConfigSetValues("dogServer", dogServer);

        }

    }

}