求.net（C#）读写config配置文件的经典实例

configurationmanager.connectionstrings[connectionname].connectionstring这是获携运取连接字符串

下面是添加连辩野梁接字脊轮符串

connectionstringsettings

s=new

connectionstringsettings("stringname","datasource=......")

configurationmanager.connectionstrings.add(s)

相应的

configurationmanager.appsettings.keys和这个configurationmanager.appsettings.add是对appsetting配置读取和写入

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，厅粗开发人员可以扮让镇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

///滑漏</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)

}

}

}

在开发Web项目的时候，会有一个配置文件Web.config，用来存放一些全局

的变量，如连接数据库用的字符串。相应的，在开发winform程序时，也念或有一个配置文件，它就是App.config，这个文件的作用与

Web.config大致相同，也可以用来存放程序所用的全局变量及Value值。

来看一个app.config文件的例子：

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

<configuration>

<appSettings>

<!--图片存放路径-->

<add key="ImgPath" value="D:\img\" />

</appSettings>

</configuration>

可以看出，app.config和web.config一样，嗯，它也是一个XML文件。那怎么对这个文件中的元素进行读取 *** 作呢？很简单，来看代码：

string strPath = System.Configuration.ConfigurationSettings.AppSettings["ImgPath"].ToString()

这样就可以把app.config文件中ImgPath这个元素的Value值读取出来了。那怎么改写元素的值呢？如果你认为像读那样的去写，像这样的代码：

System.Configuration.ConfigurationSettings.AppSettings["磨链ImgPath"] = @"E:\img\"//这样写是没用的

在对app.config文件的元素Value值进行修改 *** 作时，只能把app.config文件当作一个普通的XML文件来对待，仔游伍利用

System.Xml.XmlDocument类把这个app.config文件读到内存中，并通过System.Xml.XmlNode类找到

appSettings节点，通过System.Xml.XmlElement类找到节点下的某个元素，利用SetAttribute方法来修改这个元素

的值后，最后再将app.config文件保存到原的目录中，这样，才算完成了对一个元素Value值的修改 *** 作。下面这个方法可完成对

app.config文件appSettings节点下任意一个元素进行修改，当然，你也可能修改这个方法，达到修改任意节点，任意元素的Value值。

public static void SetValue(string AppKey, string AppValue)

{

System.Xml.XmlDocument xDoc = new System.Xml.XmlDocument()

xDoc.Load(System.Windows.Forms.Application.ExecutablePath + ".config")

System.Xml.XmlNode xNode

System.Xml.XmlElement xElem1

System.Xml.XmlElement xElem2

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

xElem1 = (System.Xml.XmlElement)xNode.SelectSingleNode("//add[@key='" + AppKey + "']")

if (xElem1 != null) xElem1.SetAttribute("value", AppValue)

else

{

xElem2 = xDoc.CreateElement("add")

xElem2.SetAttribute("key", AppKey)

xElem2.SetAttribute("value", AppValue)

xNode.AppendChild(xElem2)

}

xDoc.Save(System.Windows.Forms.Application.ExecutablePath + ".config")

}

注意这个方法中if条件else下的语句，当在文件中没有找到给定的元素时，方法会创建这个元素。

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