【Excel】VBAマクロでシートの存在チェック・確認（複数も）し、なければ作成や削除（あれば）する方法【WorksheetExists, CreateSheetWithNumber, DeleteIfExists】

Function AruKaNa(shtName As String, Optional wb As Workbook) As Boolean
    Dim shtCheck As Worksheet
    If wb Is Nothing Then Set wb = ThisWorkbook
    On Error Resume Next
    Set shtCheck = wb.Sheets(shtName)
    On Error GoTo 0
    AruKaNa = Not shtCheck Is Nothing
End Function

Sub TsukuruYo(shtName As String)
    Dim kazoeru As Integer
    kazoeru = 1
    While AruKaNa(shtName & kazoeru)
        kazoeru = kazoeru + 1
    Wend
    ThisWorkbook.Sheets.Add(After:=ThisWorkbook.Sheets(ThisWorkbook.Sheets.Count)).Name = shtName & kazoeru
End Sub

Sub KesuKamo(shtName As String, Optional wb As Workbook)
    If wb Is Nothing Then Set wb = ThisWorkbook
    If AruKaNa(shtName, wb) Then
        Application.DisplayAlerts = False
        wb.Sheets(shtName).Delete
        Application.DisplayAlerts = True
    End If
End Sub