gistfile1.cs

    private static Array DownCastArray<TE>( TE[] ar, Type elementType ) {
      Array castDown = Array.CreateInstance( elementType, ar.Length );
      for ( int i = 0; i < ar.Length; i++ ) {
        object value = ar[i];
        if ( !elementType.IsInstanceOfType( value ) ) {
          throw new ArgumentException( "df" );
        }
        castDown.SetValue( value, i );
      }
      return castDown;
    }