Nested Configuration Section app.config

Question

I don't find any examples of how to access such a nested configuration section in a app.config

  <my.configuration>     <emailNotification>       <to value="[email protected]" />       <from value="[email protected]" />       <subject value="Subject" />       <smtpHost value="smtp.you.com" />       <triggers>         <add name="1" varAlias="Var1" lower="-200" upper="-150"/>       </triggers>       </emailNotification>   </my.configuration> 

I used ConfigurationElementCollection and ConfigurationElement before. But I don't know how to do the above?

Answer 1

You need to:

Define my.configuration as section group and emailNotification as a section within the group. Add following to the configuration file:

<configSections>     <sectionGroup name="my.configuration"                   type="SectionGroupRetrieval.MyConfigurationGroup, SectionGroupRetrieval">         <section name="emailNotification"                  type="SectionGroupRetrieval.EmailNotificationSection, SectionGroupRetrieval" />     </sectionGroup>        </configSections> 

Implement the configuration section group (my.configuration).

public class MyConfigurationGroup : ConfigurationSectionGroup {     [ConfigurationProperty( "emailNotification" )]     public EmailNotificationSection EmailNotification     {         get { return (EmailNotificationSection)base.Sections[ "emailNotification" ]; }     } } 

Implement the configuration section (emailNotification).

public class EmailNotificationSection : ConfigurationSection {     [ConfigurationProperty( "to" )]     public ValueElement To     {         get { return (ValueElement)base[ "to" ]; }     }      [ConfigurationProperty( "from" )]     public ValueElement From     {         get { return (ValueElement)base[ "from" ]; }     }      [ConfigurationProperty( "subject" )]     public ValueElement Subject     {         get { return (ValueElement)base[ "subject" ]; }     }      [ConfigurationProperty( "smtpHost" )]     public ValueElement SmtpHost     {         get { return (ValueElement)base[ "smtpHost" ]; }     }      [ConfigurationProperty( "triggers" )]     public TriggerElementCollection Triggers     {         get { return (TriggerElementCollection)base[ "triggers" ]; }     } } 

Implement necessary configuration elements and configuration element collection.

public class ValueElement : ConfigurationElement {     [ConfigurationProperty( "value" )]     public string Value     {         get { return (string)base[ "value" ]; }         set { base[ "value" ] = value; }     } }  public class TriggerElement : ConfigurationElement {     [ConfigurationProperty( "name" )]     public string Name     {         get { return (string)base[ "name" ]; }         set { base[ "name" ] = value; }     }      [ConfigurationProperty( "varAlias" )]     public string VarAlias     {         get { return (string)base[ "varAlias" ]; }         set { base[ "varAlias" ] = value; }     }      [ConfigurationProperty( "lower" )]     public int Lower     {         get { return (int)base[ "lower" ]; }         set { base[ "lower" ] = value; }     }      [ConfigurationProperty( "upper" )]     public int Upper     {         get { return (int)base[ "upper" ]; }         set { base[ "upper" ] = value; }     } }  [ConfigurationCollection( typeof( TriggerElement ) )] public class TriggerElementCollection : ConfigurationElementCollection {     public TriggerElement this[ string name ]     {         get { return (TriggerElement)base.BaseGet( name ); }     }      public TriggerElement this[ int index ]     {         get { return (TriggerElement)base.BaseGet( index ); }     }      protected override ConfigurationElement CreateNewElement()     {         return new TriggerElement();     }      protected override object GetElementKey( ConfigurationElement element )     {         return ( (TriggerElement)element ).Name;     } } 

After updating the configuration file and implementing necessary configuration bits, you can access you section as follows:

Configuration config = ConfigurationManager.OpenExeConfiguration( ConfigurationUserLevel.None ); MyConfigurationGroup myConfiguration = (MyConfigurationGroup)config.GetSectionGroup( "my.configuration" ); EmailNotificationSection section = myConfiguration.EmailNotification;