详解C#如何读写config配置文件

配置文件概述：

应用程序配置文件是标准的 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。配置文件的根节点是configuration。我们经常访问的是appSettings，它是由.Net预定义的配置节。我们经常使用的配置文件的架构是客诉下面的形式。先大概有个印象，通过后面的实例会有一个比较清楚的认识。下面的“配置节”可以理解为进行配置一个XML的节点。

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);   }  } }

来源：https://www.cnblogs.com/luxiaoxun/p/3599341.html