The content type is in use

using System;
using System.Collections.Generic;
using Microsoft.SharePoint;

namespace Test
{
   class ConsoleApp
   {
      staticvoid Main(string[] args)
      {
         using (SPSite siteCollection = new SPSite("http://localhost"))
         {
            using (SPWeb webSite = siteCollection.OpenWeb())
            {
               // Get the obsolete content type.
               SPContentType obsolete = webSite.ContentTypes["Test"];

               // We have a content type.if (obsolete != null)
               {
                  IList usages = SPContentTypeUsage.GetUsages(obsolete);

                  // It is in use.if (usages.Count > 0)
                  {
                     Console.WriteLine("The content type is in use in the following locations:");
                     foreach (SPContentTypeUsage usage in usages)
                        Console.WriteLine(usage.Url);
                  }

                  // The content type is not in use.else
                  {

                     // Delete it.
                     Console.WriteLine("Deleting content type {0}...", obsolete.Name);
                     webSite.ContentTypes.Delete(obsolete.Id);
                  }
               }

               // No content type found.else
               {
                  Console.WriteLine("The content type does not exist in this site collection.");
               }
            }
         }
         Console.Write("\nPress ENTER to continue...");
         Console.ReadLine();
      }
   }
}