通过本地exe.config进行配置并修改

//本机config操作
 Configuration configs = System.Configuration.ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
                configs.AppSettings.Settings.Remove("Version_Number");
                configs.AppSettings.Settings.Add("Version_Number", newNumber);
                //一定要记得保存，写不带参数的config.Save()也可以
                configs.Save();
                //刷新，否则程序读取的还是之前的值（可能已装入内存）
                System.Configuration.ConfigurationManager.RefreshSection("appSettings");
//操作其他程序的config
                string configPath = Application.StartupPath + @"WindowsFormsApp1.exe.config";//获取到主程序的config，进行修改版本
                ExeConfigurationFileMap map = new ExeConfigurationFileMap();
                map.ExeConfigFilename = configPath;
                Configuration config = ConfigurationManager.OpenMappedExeConfiguration(map, ConfigurationUserLevel.None);
                config.AppSettings.Settings.Remove("Version_Number");
                config.AppSettings.Settings.Add("Version_Number", newNumber);
                //一定要记得保存，写不带参数的config.Save()也可以
                config.Save();
                //刷新，否则程序读取的还是之前的值（可能已装入内存）
                System.Configuration.ConfigurationManager.RefreshSection("appSettings");

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <appSettings>
    <add key="Version_Number" value="1"/>
  </appSettings>
</configuration>