代碼如下：

復制代碼代碼如下:

public static string Config(string key)  
       {  
           ExeConfigurationFileMap file = new ExeConfigurationFileMap();  
           file.ExeConfigFilename = @"Providers\\Provider.config";  
           Configuration config = ConfigurationManager.OpenMappedExeConfiguration(file, ConfigurationUserLevel.None);  
           AppSettingsSection appsection = (AppSettingsSection)config.GetSection("appSettings");  
           return appsection.Settings[key].Value;  
       }  

配置文件目錄結構：

復制代碼代碼如下:

<?xml version="1.0" encoding="utf-8" ?>  
<configuration>  
    <appSettings>  
        <add key="ConnectionString" value="Server=(local);Database=DB;User Id=sa;Password=123" />  
    </appSettings>  
</configuration>  

調用：

復制代碼代碼如下:

//里面的參數為配置文件的key   
string strConn=Config("ConnectionString");