using System.Collections.Generic;
using System.Configuration;namespace BinGoo
{public class ConfigHelper{///<summary> ///依据连接串名字connectionName返回数据连接字符串  ///</summary> ///<param name="connectionName"></param> ///<returns></returns> public static string GetConnectionStringsConfig(string connectionName){string connectionString =ConfigurationManager.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){bool isModified = 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 (ConfigurationManager.ConnectionStrings[newName] != null){isModified = true;}//新建一个连接字符串实例  ConnectionStringSettings mySettings =new ConnectionStringSettings(newName, newConString, newProviderName);// 打开可执行的配置文件*.exe.config  Configuration config =ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);// 如果连接串已存在，首先删除它  if (isModified){config.ConnectionStrings.ConnectionStrings.Remove(newName);}// 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");}public static List<string> GetAppConfigList(string ch){List<string> listKeyStr = new List<string>();listKeyStr.Clear();foreach (string key in ConfigurationManager.AppSettings){if (key.Length > ch.Length){if (key.Substring(0, ch.Length).Equals(ch))listKeyStr.Add(key + "：" + ConfigurationManager.AppSettings[key]);}}return listKeyStr;}///<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){foreach (string key in ConfigurationManager.AppSettings){if (key == strKey){return ConfigurationManager.AppSettings[strKey];}}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){bool isModified = false;foreach (string key in ConfigurationManager.AppSettings){if (key == newKey){isModified = true;}}// 打开应用程序配置文件 Configuration config =ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);//删除对象if (isModified){config.AppSettings.Settings.Remove(newKey);}// 添加节点config.AppSettings.Settings.Add(newKey, newValue);// 保存app.config文件config.Save(ConfigurationSaveMode.Modified);//强制重新加载ConfigurationManager.RefreshSection("appSettings");}}}

配置文档App.Config内容格式：

<?xml version="1.0" encoding="utf-8"?><configuration> <configSections>  </configSections>  <connectionStrings>   <add name="ConnStr" connectionString="user id =数据库账号;password=数据库密码;initial catalog=数据库名称;Server=127.0.0.1"/> </connectionStrings>  <!--系统参数配置--> <appSettings><add key="Debug" value="true"/><add key="SocketIp" value="127.0.0.1"/><add key="ServerPort" value="5000"/></appSettings><startup><supportedRuntime version="v2.0.50727"/></startup>
</configuration>

其中配置文件中添加配置格式：
<add key="配置名称" value="配置的值"/>