VB.NETテキストボックス（TextBox）

TextBoxで入力制御の例を説明します。

仕様説明

・[↑][↓]は前・次のコントロールに移動する

・[TAB]は機能しない

・[ESC]は入力初期値に戻す

・確定は[Enter]とする

・マウス移動は入力キャンセルとする

・セットフォーカスは全選択とする

金額入力の例

Private Sub TextBox1_Enter(sender As Object, e As EventArgs) Handles TextBox1.Enter
    DirectCast(sender, TextBox).ClearUndo()
    DirectCast(sender, TextBox).SelectAll()
End Sub

Private Sub TextBox1_Leave(sender As Object, e As EventArgs) Handles TextBox1.Leave
    DirectCast(sender, TextBox).Undo()
End Sub

Private Sub TextBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox1.KeyPress
    If e.KeyChar = ControlChars.Back Then
        Return
    End If

    If Not Char.IsDigit(e.KeyChar) Then
        e.Handled = True
    End If

    Dim s As String = StrConv(e.KeyChar, VbStrConv.Narrow)
    e.KeyChar = s(0)
End Sub

Private Sub TextBox1_PreviewKeyDown(sender As Object, e As PreviewKeyDownEventArgs) Handles TextBox1.PreviewKeyDown
    Select Case e.KeyCode
        Case Keys.Up
            Me.ProcessTabKey(False)
        Case Keys.Down
            Me.ProcessTabKey(True)
        Case Keys.Tab
            e.IsInputKey = True
        Case Keys.Escape
            DirectCast(sender, TextBox).Undo()
            DirectCast(sender, TextBox).ClearUndo()
        Case Keys.Enter
            Dim val As Integer
            Dim bc As Boolean = Integer.TryParse(DirectCast(sender, TextBox).Text,
                                                 System.Globalization.NumberStyles.Number,
                                                 System.Globalization.CultureInfo.InvariantCulture, val)

            DirectCast(sender, TextBox).Text = val.ToString("#,0")
            DirectCast(sender, TextBox).ClearUndo()
            Me.ProcessTabKey(True)
            e.IsInputKey = True
    End Select
End Sub

実数入力例

Private Sub TextBox1_Enter(sender As Object, e As EventArgs) Handles TextBox1.Enter
    DirectCast(sender, TextBox).ClearUndo()
    DirectCast(sender, TextBox).SelectAll()
End Sub

Private Sub TextBox1_Leave(sender As Object, e As EventArgs) Handles TextBox1.Leave
    DirectCast(sender, TextBox).Undo()
End Sub

Private Sub TextBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox1.KeyPress
    If e.KeyChar = ControlChars.Back Then
        Return
    End If

    Dim s As String = StrConv(e.KeyChar, VbStrConv.Narrow)
    If Not Char.IsDigit(e.KeyChar) And s <> "." Then
        e.Handled = True
    End If

    e.KeyChar = s(0)
End Sub

Private Sub TextBox1_KeyDown(sender As Object, e As KeyEventArgs) Handles TextBox1.KeyDown
    Select Case e.KeyCode
        Case Keys.Up
            Me.ProcessTabKey(False)
        Case Keys.Down
            Me.ProcessTabKey(True)
        Case Keys.Tab
            e.Handled = False
        Case Keys.Escape
            DirectCast(sender, TextBox).Undo()
            DirectCast(sender, TextBox).ClearUndo()
        Case Keys.Enter
            Dim val As Decimal
            Dim bc As Boolean = Decimal.TryParse(DirectCast(sender, TextBox).Text,
                                             System.Globalization.NumberStyles.Number,
                                             System.Globalization.CultureInfo.InvariantCulture, val)

            DirectCast(sender, TextBox).Text = val.ToString("#,0.00")
            DirectCast(sender, TextBox).ClearUndo()
            Me.ProcessTabKey(True)
            e.Handled = False
    End Select
End Sub

日付入力例

Private Sub TextBox2_Enter(sender As Object, e As EventArgs) Handles TextBox2.Enter
    DirectCast(sender, TextBox).ClearUndo()
    DirectCast(sender, TextBox).SelectAll()
End Sub

Private Sub TextBox2_Leave(sender As Object, e As EventArgs) Handles TextBox2.Leave
    DirectCast(sender, TextBox).Undo()
End Sub

Private Sub TextBox2_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox2.KeyPress
    If e.KeyChar = ControlChars.Back Then
        Return
    End If

    Dim s As String = StrConv(e.KeyChar, VbStrConv.Narrow)

    If Not Char.IsDigit(s(0)) And s <> "/" Then
        e.Handled = True
    End If

    e.KeyChar = s(0)
End Sub

Private Sub TextBox2_PreviewKeyDown(sender As Object, e As PreviewKeyDownEventArgs) Handles TextBox2.PreviewKeyDown
    Select Case e.KeyCode
        Case Keys.Up
            Me.ProcessTabKey(False)
        Case Keys.Down
            Me.ProcessTabKey(True)
        Case Keys.Tab
            e.IsInputKey = True
        Case Keys.Escape
            DirectCast(sender, TextBox).Undo()
            DirectCast(sender, TextBox).ClearUndo()
        Case Keys.Enter
            Dim s As String = DirectCast(sender, TextBox).Text

            Dim val As Integer
            If Integer.TryParse(s, System.Globalization.NumberStyles.Number,
                                   System.Globalization.CultureInfo.InvariantCulture, val) Then
                s = Format(val, "####/00/00")
            End If

            Dim dt As DateTime
            If Not DateTime.TryParse(s, New System.Globalization.CultureInfo("ja-JP"),
                                        System.Globalization.DateTimeStyles.AssumeLocal, dt) Then
                Return
            End If

            DirectCast(sender, TextBox).Text = dt.ToString("yyyy/MM/dd")

            DirectCast(sender, TextBox).ClearUndo()
            Me.ProcessTabKey(True)
            e.IsInputKey = True
    End Select
End Sub

※上記の例では、クリップボードの制御をしていません。

・上記の例ではKeyDownとPreviewKeyDownを使用していますが、通常KeyDownでよいようです。PreviewKeyDownはButtonなどの時に使用します。