【VBA】Day関数の構文と使用例

Sub daySample2()
    Dim date1 As Date, date2 As Date
    ' 現在の日付
    date1 = Date
    ' 日付を指定
    date2 = #10/10/2023#
    
    Debug.Print date1 & " の日付は " & Day(date1)
    Debug.Print date2 & " の日付は " & Day(date2)
    
End Sub

2023/10/12 の日付は 12
2023/10/10 の日付は 10

Sub daySample3()
    Dim date1 As Date, date2 As Date
    
    date1 = #10/21/2023#
    date2 = #12/3/2023#
    
    Debug.Print date1 & " の日付は " & Right("0" & Day(date1), 2)
    Debug.Print date2 & " の日付は " & Right("0" & Day(date2), 2)
    
End Sub

2023/10/21 の日付は 21
2023/12/03 の日付は 03

Sub daySample1()
    Dim cell1 As Range, cell2 As Range
    
    With Sheets("sheet1")
        Set cell1 = Sheets("sheet1").Cells(2, 2)
        Set cell2 = Sheets("sheet1").Cells(3, 2)
    End With
    
    cell1.Offset(0, 2).Value = Day(cell1.Value) & "日"
    cell2.Offset(0, 2).Value = Day(cell2.Value) & "日"
End Sub

Sub daySample4()
    Dim db As Database
    Dim rs As Recordset
    
    Set db = CurrentDb()
    Set rs = db.OpenRecordset("サンプルテーブル", dbOpenTable)
    
    With rs
        Do Until .EOF
            Debug.Print .Fields("日付フィールド") & _
                    "⇒" & _
                    Day(.Fields("日付フィールド")) & _
                    "日"
            .MoveNext
        Loop
    End With
    
    rs.Close: Set rs = Nothing
    Set db = Nothing
End Sub

2023/12/01⇒1日
2021/11/05⇒5日
1999/10/10⇒10日
1975/08/08⇒8日