[c#] How to delete object?

I would suggest , to use .Net's IDisposable interface if your are thinking of to release instance after its usage.

See a sample implementation below.

public class Car : IDisposable
{

   public void Dispose()
   {  
      Dispose(true);
       // any other managed resource cleanups you can do here
       Gc.SuppressFinalize(this);
   }
   ~Car()      // finalizer
   {
        Dispose(false);
   }

   protected virtual void Dispose(bool disposing)
   {
     if (!_disposed)
     {
      if (disposing)
      {
        if (_stream != null) _stream.Dispose(); // say you have to dispose a stream
      }

      _stream = null;
    _disposed = true;
    }

   }
}

Now in your code:

void main()
{
   using(var car = new Car())
   {
     // do something with car
   } // here dispose will automtically get called. 
}