Using Custom Configuration in Web.config of ASP.NET MVC Application

In this article, you will see how to store custom configuration in web.config of an ASP.NET MVC application.

Appsettings

In web.config file you can store configuration information in appsettings as key value pair and read it in the application.

Store it

<appsettings>
	<add key="Appname" value="MyAspnetApp" />
</appsettings>

Read it System.Configuration.ConfigurationManager.AppSettings["AppName"]

ConnectionStrings

Connection strings can also be stored as key/value pairs in the connectionStrings section of the configuration element of an application configuration file.

Store it

<connectionStrings>  
	<add name="AppConnection"
		providerName="System.Data.ProviderName"
		connectionString="Valid Connection String;" />  
</connectionStrings>

Read it System.Configuration.ConfigurationManager.ConnectionStrings["AppConnection"]

Custom Configuration

You can also store custom xml configuration in web.config file. You need to create a custom configuration section handler that inherits from System.Configuration.ConfigurationSection

In this example you will add necessary code to store custom config like this

<webappInfo title="abc company">
  <contact name="admin" email="admin@domain.com"/>
  <offices>
    <add location="india" address="123 india" />
    <add location="usa" address="123 usa" />
  </offices>
</webappInfo>

This xml information is then mapped to model classes with the help of attributes.

Create a new asp.net web application (.Net framework) and choose MVC template
Create new folder Utils in the project
Create new file ContactElement.cs. This class inherits from ConfigurationElement. The information from contact element is mapped to this class

public class ContactElement : ConfigurationElement
{
    [ConfigurationProperty("name")]
    public String Name
    {
        get
        {
            return (String)this["name"];
        }
        set
        {
            this["name"] = value;
        }
    }

    [ConfigurationProperty("email")]
    public String Email
    {
        get
        {
            return (String)this["email"];
        }
        set
        {
            this["email"] = value;
        }
    }
}

Name and Email property are decorated with ConfigurationProperty attribute specifying the xml attribute name
Create OfficeElement.cs to add information about the offices.

public class OfficeElement : ConfigurationElement
{

    [ConfigurationProperty("location")]
    public String Location
    {
        get
        {
            return (String)this["location"];
        }
        set
        {
            this["location"] = value;
        }
    }

    [ConfigurationProperty("address")]
    public String Address
    {
        get
        {
            return (String)this["address"];
        }
        set
        {
            this["address"] = value;
        }
    }
}

Create OfficeCollection.cs. This class inherits from ConfigurationElementCollection and is used for adding a collection of office element

public class OfficeCollection: ConfigurationElementCollection
{
   protected override ConfigurationElement CreateNewElement()
   {
       return new OfficeElement();
   }

   protected override object GetElementKey(ConfigurationElement element)
   {
       return ((OfficeElement)element).Location;
   }
}

Create WebAppInfoSection.cs. This class inherits from ConfigurationSection and is used to define custom section in web.config

public class WebAppInfoSection : ConfigurationSection
{
    [ConfigurationProperty("title")]
     public string Title
     {
         get
         {
             return (string)this["title"];
         }
         set
         { 
             this["title"] = value; 
         }
     }

    [ConfigurationProperty("contact")]
    public ContactElement Contact
    {
        get
        {
            return (ContactElement)this["contact"];
        }
        set
        { this["contact"] = value; }
    }


    [ConfigurationProperty("offices")]
    [ConfigurationCollection(typeof(OfficeCollection))]
    public OfficeCollection Offices
    {
        get
        {
            OfficeCollection officeCollection = (OfficeCollection)this["offices"];
            return officeCollection;
        }

        set
        {
            this["offices"] = value;
        }
    }
}

In web.config files, add a new section with name webappInfo

<configSections>
    <section name="webappInfo" type="AspnetMvcCodeSamples.Utils.WebAppInfoSection" />
</configSections>

Then add custom section configuration

<webappInfo title="abc company">
    <contact name="admin" email="admin@domain.com"/>
    <offices>
      <add location="india" address="123" />
      <add location="usa" address="123" />
    </offices>
  </webappInfo>

In HomeController.cs, read the section information using

var config = (WebAppInfoSection)System.Configuration.ConfigurationManager.GetSection("webappInfo");
var output = new StringBuilder($"Title: {config.Title}, Contact: {config.Contact.Name} {config.Contact.Email}<br/>");
            
foreach (var item in config.Offices)
{
    var office = (OfficeElement)item;
    output.AppendLine($"Office: {office.Location} {office.Address} <br/>");
}

Custom Section Group

You can also add custom section group

 <sectionGroup name="webappInfoGroup">
   <section 
     name="webappInfo" 
     type="AspnetMvcCodeSamples.Utils.WebAppInfoSection" 
     allowLocation="true" 
     allowDefinition="Everywhere"
   />
 </sectionGroup>
<webappInfoGroup>
  <webappInfo title="abc company">
    <contact name="admin" email="admin@domain.com"/>
    <offices>
      <add location="india" address="123" />
      <add location="usa" address="123" />
    </offices>
  </webappInfo>
</webappInfoGroup>

To read it var config = (WebAppInfoSection)System.Configuration.ConfigurationManager.GetSection("webappInfoGroup/webappInfo ");

Try Sample

Home Page - Expeo Tutorials - ASP.NET Angular Code Samples (expeoaspnetmvccodesamples.azurewebsites.net)

Access Code

expeo-in/AspnetAngularCodeSamples: Asp.net Angular Code Samples (github.com)