求各位给详细解释一下这个代码的各个意思!!每行都要!!谢谢了
Private Sub clock(ByRef kk As Double)
Dim t2 As String
Dim t1 As String
Dim hr As Object
Dim t As String
t = TimeString
hr = Val(Mid(t, 1, 2)) + kk
If hr >= 24 Then hr = hr - 24
t1 = Str(hr)
t2 = Mid(t, 3, 6)
Label1.Text = t1 & t2
Beep()
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Select Case ComboBox1.Text
Case "北京"
clock((0))
Case "上海"
clock((0))
Case "东京"
clock((1))
Case "纽约"
clock((11))
Case "伦敦"
clock((16))
End Select
End Sub