C#读写config配置文件

应用程序配置文件（App.config）是标准的 XML 文件，XML 标记和属性是区分大小写的。它是可以按需要更改的，开发人员可以使用配置文件来更改设置，而不必重编译应用程序。

对于一个config文件：

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

<configuration>

  <appSettings>

    <add key="ServerIP" value="127.0.0.1"></add>

    <add key="DataBase" value="WarehouseDB"></add>

    <add key="user" value="sa"></add>

    <add key="password" value="sa"></add>

  </appSettings>

</configuration>

对config配置文件的读写类：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Text.RegularExpressions;

using System.Configuration;

using System.ServiceModel;

using System.ServiceModel.Configuration;



namespace NetUtilityLib

{

    public static class ConfigHelper

    {

        //依据连接串名字connectionName返回数据连接字符串  

        public static string GetConnectionStringsConfig(string connectionName)

        {

            //指定config文件读取

            string file = System.Windows.Forms.Application.ExecutablePath;

            System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(file);

            string connectionString =

                config.ConnectionStrings.ConnectionStrings[connectionName].ConnectionString.ToString();

            return connectionString;

        }



        ///<summary> 

        ///更新连接字符串  

        ///</summary> 

        ///<param name="newName">连接字符串名称</param> 

        ///<param name="newConString">连接字符串内容</param> 

        ///<param name="newProviderName">数据提供程序名称</param> 

        public static void UpdateConnectionStringsConfig(string newName, string newConString, string newProviderName)

        {

            //指定config文件读取

            string file = System.Windows.Forms.Application.ExecutablePath;

            Configuration config = ConfigurationManager.OpenExeConfiguration(file);



            bool exist = false; //记录该连接串是否已经存在  

            //如果要更改的连接串已经存在  

            if (config.ConnectionStrings.ConnectionStrings[newName] != null)

            {

                exist = true;

            }

            // 如果连接串已存在，首先删除它  

            if (exist)

            {

                config.ConnectionStrings.ConnectionStrings.Remove(newName);

            }

            //新建一个连接字符串实例  

            ConnectionStringSettings mySettings =

                new ConnectionStringSettings(newName, newConString, newProviderName);

            // 将新的连接串添加到配置文件中.  

            config.ConnectionStrings.ConnectionStrings.Add(mySettings);

            // 保存对配置文件所作的更改  

            config.Save(ConfigurationSaveMode.Modified);

            // 强制重新载入配置文件的ConnectionStrings配置节  

            ConfigurationManager.RefreshSection("ConnectionStrings");

        }



        ///<summary> 

        ///返回*.exe.config文件中appSettings配置节的value项  

        ///</summary> 

        ///<param name="strKey"></param> 

        ///<returns></returns> 

        public static string GetAppConfig(string strKey)

        {

            string file = System.Windows.Forms.Application.ExecutablePath;

            Configuration config = ConfigurationManager.OpenExeConfiguration(file);

            foreach (string key in config.AppSettings.Settings.AllKeys)

            {

                if (key == strKey)

                {

                    return config.AppSettings.Settings[strKey].Value.ToString();

                }

            }

            return null;

        }



        ///<summary>  

        ///在*.exe.config文件中appSettings配置节增加一对键值对  

        ///</summary>  

        ///<param name="newKey"></param>  

        ///<param name="newValue"></param>  

        public static void UpdateAppConfig(string newKey, string newValue)

        {

            string file = System.Windows.Forms.Application.ExecutablePath;

            Configuration config = ConfigurationManager.OpenExeConfiguration(file);

            bool exist = false;

            foreach (string key in config.AppSettings.Settings.AllKeys)

            {

                if (key == newKey)

                {

                    exist = true;

                }

            }

            if (exist)

            {

                config.AppSettings.Settings.Remove(newKey);

            }

            config.AppSettings.Settings.Add(newKey, newValue);

            config.Save(ConfigurationSaveMode.Modified);

            ConfigurationManager.RefreshSection("appSettings");

        }



        // 修改system.serviceModel下所有服务终结点的IP地址

        public static void UpdateServiceModelConfig(string configPath, string serverIP)

        {

            Configuration config = ConfigurationManager.OpenExeConfiguration(configPath);

            ConfigurationSectionGroup sec = config.SectionGroups["system.serviceModel"];

            ServiceModelSectionGroup serviceModelSectionGroup = sec as ServiceModelSectionGroup;

            ClientSection clientSection = serviceModelSectionGroup.Client;

            foreach (ChannelEndpointElement item in clientSection.Endpoints)

            {

                string pattern = @"\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b";

                string address = item.Address.ToString();

                string replacement = string.Format("{0}", serverIP);

                address = Regex.Replace(address, pattern, replacement);

                item.Address = new Uri(address);

            }



            config.Save(ConfigurationSaveMode.Modified);

            ConfigurationManager.RefreshSection("system.serviceModel");

        }



        // 修改applicationSettings中App.Properties.Settings中服务的IP地址

        public static void UpdateConfig(string configPath, string serverIP)

        {

            Configuration config = ConfigurationManager.OpenExeConfiguration(configPath);

            ConfigurationSectionGroup sec = config.SectionGroups["applicationSettings"];

            ConfigurationSection configSection = sec.Sections["DataService.Properties.Settings"];

            ClientSettingsSection clientSettingsSection = configSection as ClientSettingsSection;

            if (clientSettingsSection != null)

            {

                SettingElement element1 = clientSettingsSection.Settings.Get("DataService_SystemManagerWS_SystemManagerWS");

                if (element1 != null)

                {

                    clientSettingsSection.Settings.Remove(element1);

                    string oldValue = element1.Value.ValueXml.InnerXml;

                    element1.Value.ValueXml.InnerXml = GetNewIP(oldValue, serverIP);

                    clientSettingsSection.Settings.Add(element1);

                }



                SettingElement element2 = clientSettingsSection.Settings.Get("DataService_EquipManagerWS_EquipManagerWS");

                if (element2 != null)

                {

                    clientSettingsSection.Settings.Remove(element2);

                    string oldValue = element2.Value.ValueXml.InnerXml;

                    element2.Value.ValueXml.InnerXml = GetNewIP(oldValue, serverIP);

                    clientSettingsSection.Settings.Add(element2);

                }

            }

            config.Save(ConfigurationSaveMode.Modified);

            ConfigurationManager.RefreshSection("applicationSettings");

        }



        private static string GetNewIP(string oldValue, string serverIP)

        {

            string pattern = @"\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b";

            string replacement = string.Format("{0}", serverIP);

            string newvalue = Regex.Replace(oldValue, pattern, replacement);

            return newvalue;

        }

    }

}

测试代码如下：

    class Program

    {

        static void Main(string[] args)

        {

            try

            {

                //string file = System.Windows.Forms.Application.ExecutablePath + ".config";

                //string file1 = AppDomain.CurrentDomain.SetupInformation.ConfigurationFile;

                string serverIP = ConfigHelper.GetAppConfig("ServerIP");

                string db = ConfigHelper.GetAppConfig("DataBase");

                string user = ConfigHelper.GetAppConfig("user");

                string password = ConfigHelper.GetAppConfig("password");



                Console.WriteLine(serverIP);

                Console.WriteLine(db);

                Console.WriteLine(user);

                Console.WriteLine(password);



                ConfigHelper.UpdateAppConfig("ServerIP", "192.168.1.11");

                string newIP = ConfigHelper.GetAppConfig("ServerIP");

                Console.WriteLine(newIP);



                Console.ReadKey();

            }

            catch (Exception ex)

            {

                Console.WriteLine(ex.Message);

            }

        }

    }