バーコードで在庫調べする方法。エクセルＶＢＡのシートイベントを使う

Private Sub Worksheet_Activate()

    Range("A1") = "書誌コードＮＯ"
    Range("B1") = "価格コードＮＯ"
    Range("E1") = "項目修正スイッチ"
    With Range("A:E")
        .EntireColumn.AutoFit
    End With
    Range("C1").Select

End Sub

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

Dim R As Long
Dim LARow As Long
Dim LARowb As Long
Dim p As Variant, q As Variant, w As Variant
Dim AD As Variant
Dim x As Integer, y As Integer

With Range("A:B")
    .NumberFormatLocal = "@"
    .EntireColumn.AutoFit
End With

If Target.Column <> 2 And Target.Column <> 1 Then
    R = MsgBox("A列のセルをアクティブにしてください。", vbOKOnly + vbExclamation)
    If Target.Column = 5 Then
        q = Application.inputbox(Prompt:="Ａ列の修正コードを入力。" & vbCrLf & "Ｂ列修正または間違いの場合はキャンセルを" & vbCrLf & "空欄入力は9999を", Type:=2)
            If q = False Or q = "" Then
                w = Application.inputbox(Prompt:="Ｂ列の修正コードを入力。" & vbCrLf & "間違いの場合はキャンセルを" & vbCrLf & "空欄入力は9999を", Type:=2)
                    If w = False Then
                        GoTo STEP_E
                    ElseIf w = "" Then
                        GoTo STEP_E
                    ElseIf w = 9999 Then
                        Cells(Target.Row, 2) = vbNullString
                    Else
                        Cells(Target.Row, 2) = w
                    End If
            ElseIf q = 9999 Then
                        Cells(Target.Row, 1) = vbNullString
            Else
                Cells(Target.Row, 1) = q
            End If
    End If
                
    If R = vbOK Then
        GoTo STEP_E
    End If
ElseIf Target.Column = 2 Then
        If Target.Value <> "" Then
            Target.Offset(1, -1).Select
        End If
Else
    LARow = Range("A1").CurrentRegion.Rows.Count
    LARowb = Cells(1, 1).End(xlDown).Row

    Range(Cells(1, 5), Cells(LARow, 5)).Interior.Color = RGB(230, 230, 230)
    
    If LARow = 1 Then
        Range("A2").Select
    Else
        If LARowb < LARow Then
            Range("A" & LARowb + 1).Select
        Else
            Range("A" & LARow + 1).Select
        End If
    End If
End If

AD = Target.Address(False, False)
  x = Target.Row
  y = Target.Column
  
p = Application.inputbox(Prompt:="コードを入力。" & vbCrLf & "終了の場合はキャンセルを", Type:=2)
If p = False Then
    GoTo STEP_E
ElseIf p = "" Then
    GoTo STEP_E
Else
    p = LTrim(p)
    Range(AD).Value = p
    If Left(p, 3) = 978 Then
        If Target.Column = 1 Then
            Cells(x, y + 1).Select
        Else
            Cells(x + 1, y - 1).Select
        End If
    ElseIf Left(p, 3) = "" Then
        GoTo STEP_E
    Else
        If Target.Column = 1 Then
            Cells(x + 1, y).Select
        Else
            Cells(x + 1, y - 1).Select
        End If
    End If
End If
STEP_E:
    Cells(1, 3).Select
End Sub

Private Sub Worksheet_Deactivate()
Module1.バーコード
    
End Sub