ExcelからCSVへの自動出力：VBAによる実装ガイド

Sub ExportToCSV()

    ' 変数の宣言
    Dim filePath As String
    Dim lastRow As Long
    Dim lastColumn As Long
    Dim cellData As Variant
    Dim i As Long, j As Long
    Dim ws As Worksheet
    Dim inputDate As String
    Dim userConfirm As VbMsgBoxResult
    Dim fileName As String

    ' 初期化
    Set ws = ActiveSheet
    
    ' ユーザーにCSVのファイル名を入力してもらう
    fileName = InputBox("CSVファイルの名前を入力してください。")
    
    ' ユーザーに確認
    userConfirm = MsgBox("以下のシートでCSVを作成します。よろしいですか？" & vbCrLf & vbCrLf & ws.Name, vbYesNo)
    
    ' ユーザーが「はい」と答えた場合
    If userConfirm = vbYes Then
    
        ' ファイルのパスと名前を設定
        filePath = ThisWorkbook.Path & "\" & fileName & ".csv"
        
        ' データが存在する最後の行と列を見つける
        lastRow = ws.Cells(Rows.Count, "A").End(xlUp).Row
        lastColumn = ws.Cells(1, Columns.Count).End(xlToLeft).Column
        
        ' セルの範囲を変数に読み込む
        cellData = ws.Range(ws.Cells(1, 1), ws.Cells(lastRow, lastColumn)).Value
        
        ' ファイルを出力用に開く
        Open filePath For Output As #1
        
        ' 配列の各行に対してループ
        For i = 1 To UBound(cellData, 1)
            ' 行の最初のセルを書き込む
            Print #1, CStr(cellData(i, 1));
            
            ' 行の各列に対してループ
            For j = 2 To UBound(cellData, 2)
                ' セルのデータを書き込む、カンマで区切る
                Print #1, "," & cellData(i, j);
            Next j
            
            ' CSVファイルで次の行に移動
            Print #1,
        Next i
        
        ' ファイルを閉じる
        Close #1
        
        ' CSV出力が完了したことをユーザーに通知
        MsgBox "CSV出力が成功しました。"
        
    Else
        ' ユーザーが操作をキャンセルした場合
        Exit Sub
    End If
    
    ' 元のワークシートをアクティブにする
    ws.Activate

End Sub

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