Making custom control in WPF

Question

Hello all :)

I have found a class that inherits from ComboBox. That class implements some new features to a standard ComboBox.

That Class begins like this:

 using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Input;


namespace videoteka
{
   public class FilteredComboBox : ComboBox
    {
   

        ////

        // Public Fields

        ////

 

        /// <summary>

        /// The search string treshold length.

        /// </summary>

        /// <remarks>

        /// It's implemented as a Dependency Property, so you can set it in a XAML template 

        /// </remarks>

        public static readonly DependencyProperty MinimumSearchLengthProperty =

            DependencyProperty.Register(

                "MinimumSearchLength",

and goes on (I can post the full class if someone needs it).

The question is how do I make a control that I can put it on tool box and use it like drag and drop?


Thank you in advancel.