You need to use this:
Code:
Public Class frmMain
    Dim pc() As CardPictureBox
    Public Sub New()
        InitializeComponent()
        pc = {picCard0, picCard1, picCard2, picCard3, picCard4, picCard5, picCard6, picCard7, picCard8, picCard9, picCard10, picCard11, picCard12, picCard13, picCard14, picCard15, picCard16, picCard17, picCard18, picCard19, picCard20, picCard21, picCard22}
    End Sub