C# add properties to framework class

Question

I use the Lync SDK 2013 and want to extend a specific class Contact. The contact object is able to get a displayed name by using

string displayName = contact.GetContactInformation(ContactInformationType.DisplayName);

and I want to create a new class called User which extends this contact class. For example User would have a property

public object DisplayName { get { return GetContactInformation(ContactInformationType.DisplayName); } }

that others just need to write

user.DisplayName

to get the displayed name of the contact. Unfortunately I have to setup a constructor when inheriting from Contact

    public User() : base()
    {
    }

and the constructor of Contact takes some arguments. But I don't get which arguments are needed for the base constructor.

Is it possible to write "use the same constructor" without knowing the parameters?

Otherwise I don't know where to find the constructor here

#region Assembly Microsoft.Lync.Model, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c
// projectPath\packages\Lync2013SDK.15.0.4466.1000\lib\net40\Microsoft.Lync.Model.dll
#endregion

using System;
using System.Collections.Generic;
using Microsoft.Lync.Model.Conversation;
using Microsoft.Lync.Model.Group;
using Microsoft.Lync.Model.Internal;

namespace Microsoft.Lync.Model
{
    //
    // Summary:
    //     Represents a contact within the Lync client. A contact can be person, bot or
    //     phone number.
    public class Contact : UCWFull
    {
        //
        ~Contact();

        //
        // Summary:
        //     Gets the contact URI.
        public string Uri { get; }
        //
        // Summary:
        //     Returns the Unified Communication type of this contact.
        public UnifiedCommunicationType UnifiedCommunicationType { get; }
        //
        // Summary:
        //     Gets a collection of contact settings.
        public IDictionary<ContactSetting, object> Settings { get; }
        //
        // Summary:
        //     Gets the list of all groups of which this contact is a member of.
        public GroupCollection CustomGroups { get; }
        //
        // Summary:
        //     Gets the parent Contact and Group Manager of this contact.
        public ContactManager ContactManager { get; }

        //
        // Summary:
        //     Occurs when one or more pieces of contact information are changed.
        //
        // Hints:
        //     Application logic must subscribe to contact information publication before the
        //     ContactInformationChanged event can be received. Call the CreateSubscription
        //     method on the ContactManager object and then add the Contact to be subscribed
        //     and the ContactInformationTypes that you are interested in. Finally, call the
        //     Subscribe method on the ContactSubscription object.
        public event EventHandler<ContactInformationChangedEventArgs> ContactInformationChanged;
        //
        // Summary:
        //     Occurs when the value of a contact property changes.
        public event EventHandler<ContactSettingChangedEventArgs> SettingChanged;
        //
        // Summary:
        //     Occurs when the contact URI is changed.
        public event EventHandler<UriChangedEventArgs> UriChanged;

        //
        // Summary:
        //     Sets a setting associated with this contact.
        public IAsyncResult BeginChangeSetting(ContactSetting contactSettingType, object contactSettingValue, AsyncCallback contactCallback, object state);
        //
        // Summary:
        //     Gets the Organization Info of this contact.
        public IAsyncResult BeginGetOrganizationInformation(OrganizationStructureTypes orgInfoTypes, AsyncCallback contactCallback, object state);
        //
        // Summary:
        //     Moves this contact from a source group to a target group.
        public IAsyncResult BeginMoveToGroup(Group.Group targetGroup, Group.Group sourceGroup, AsyncCallback contactCallback, object state);
        //
        // Summary:
        //     Checks if the setting can be set for this contact.
        //
        // Returns:
        //     System.Boolean
        public bool CanChangeSetting(ContactSetting contactSetting);
        //
        // Summary:
        //     Checks if this contact can be moved from a source group to a target group.
        //
        // Returns:
        //     System.Boolean
        public bool CanMoveToGroup(Group.Group targetGroup, Group.Group sourceGroup);
        //
        // Summary:
        //     Checks if this contact can start a given mode of communication (modality
        //
        // Returns:
        //     System.Boolean
        public bool CanStart(ModalityTypes modalityTypes);
        //
        // Summary:
        //     Creates a collaboration endpoint object from a telephone number.
        public ContactEndpoint CreateContactEndpoint(string telephoneUri);
        //
        // Summary:
        //     Sets a setting associated with this contact.
        public void EndChangeSetting(IAsyncResult asyncResult);
        //
        // Summary:
        //     Gets the Organization Info of this contact.
        public void EndGetOrganizationInformation(out ContactCollection managers, out ContactCollection peers, out ContactCollection directors, IAsyncResult asyncResult);
        //
        // Summary:
        //     Moves this contact from a source group to a target group.
        public void EndMoveToGroup(IAsyncResult asyncResult);
        //
        // Summary:
        //     Gets a single contact information from this contact.
        //
        // Returns:
        //     System.Object
        public object GetContactInformation(ContactInformationType contactInformationType);
        //
        // Summary:
        //     Gets contact information from this contact.
        public IDictionary<ContactInformationType, object> GetContactInformation(IEnumerable<ContactInformationType> contactInformationTypes);
    }
}

Answer 1

Instead of inheriting from the class have you considered creating an extension method

public static string DisplayName(this Contact contact)
{
     return contact.GetContactInformation(ContactInformationType.DisplayName).ToString();
}