How to create a custom configuration section in app.config?

Question

I want to add a custom configuration section to my app.config file. Is there a way to do this and how can I access these settings in my program. The following is the configuration section that I want to add to my app.config :

 <RegisterCompanies> <Companies> <Company name="Tata Motors" code="Tata"/> <Company name="Honda Motors" code="Honda"/> </Companies> </RegisterCompanies> 

Answer 1

Import namespace:

 using System.Configuration; 

Creating a configuration Company element:

 public class Company : ConfigurationElement { [ConfigurationProperty("name", IsRequired = true)] public string Name { get { return this["name"] as string; } } [ConfigurationProperty("code", IsRequired = true)] public string Code { get { return this["code"] as string; } } } 

ConfigurationElementCollection:

 public class Companies : ConfigurationElementCollection { public Company this[int index] { get { return base.BaseGet(index) as Company ; } set { if (base.BaseGet(index) != null) { base.BaseRemoveAt(index); } this.BaseAdd(index, value); } } public new Company this[string responseString] { get { return (Company) BaseGet(responseString); } set { if(BaseGet(responseString) != null) { BaseRemoveAt(BaseIndexOf(BaseGet(responseString))); } BaseAdd(value); } } protected override System.Configuration.ConfigurationElement CreateNewElement() { return new Company(); } protected override object GetElementKey(System.Configuration.ConfigurationElement element) { return ((Company)element).Name; } } 

and ConfigurationSection:

 public class RegisterCompaniesConfig : ConfigurationSection { public static RegisterCompaniesConfig GetConfig() { return (RegisterCompaniesConfig)System.Configuration.ConfigurationManager.GetSection("RegisterCompanies") ?? new RegisterCompaniesConfig(); } [System.Configuration.ConfigurationProperty("Companies")] [ConfigurationCollection(typeof(Companies), AddItemName = "Company")] public Companies Companies { get { object o = this["Companies"]; return o as Companies ; } } } 

and you must also register a new configuration section in web.config (app.config):

 <configuration> <configSections> <section name="Companies" type="blablabla.RegisterCompaniesConfig" ..> 

Then you load your config from

 var config = RegisterCompaniesConfig.GetConfig(); foreach(var item in config.Companies) { do something .. } 

Answer 2

You should check out the three-part series of Jon Rista for the .NET 2.0 configuration on CodeProject.

• Puzzles for .NET 2.0 Configuration
• Decryption Secrets of .NET 2.0 Configuration
• Breaking Secrets of .NET 2.0 Configuration

Highly recommended, well written and very helpful!

This very clearly shows how to write the necessary classes (coming from ConfigurationElement and / or ConfigurationSection ) to create the necessary configuration sections.