Question

这是我的问题。在KeyUp中

If Textbox1.Text.Length = 3 Then

Textbox1.Text = Textbox1.Text.Insert(3, "-")

Textbox1.SelectionStart = Textbox1.TextLength

End If

输出就像这样：

AAA-0123

例如，我在前3个字母输入错误，我想要改变它，但我仍然无法删除连字符

AAA-

Answer 1

也许您正在寻找MaskedTextBox？因此，您只能以此格式输入文字。

Masked Textbox MSDN

Private Sub MaskedTextBox1_MaskInputRejected(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MaskInputRejectedEventArgs) Handles MaskedTextBox1.MaskInputRejected
    If (Me.MaskedTextBox1.MaskFull) Then
        ToolTip1.ToolTipTitle = "Input Rejected - Too Much Data"
        ToolTip1.Show("You cannot enter any more data into the date field. Delete some characters in order to insert more data.", Me.MaskedTextBox1, Me.MaskedTextBox1.Location.X, Me.MaskedTextBox1.Location.Y, 5000)
    ElseIf (e.Position = Me.MaskedTextBox1.Mask.Length) Then
        ToolTip1.ToolTipTitle = "Input Rejected - End of Field"
        ToolTip1.Show("You cannot add extra characters to the end of this date field.", Me.MaskedTextBox1, 0, -20, 5000)
    Else
        ToolTip1.ToolTipTitle = "Input Rejected"
        ToolTip1.Show("You can only add numeric characters (0-9) into this date field.", Me.MaskedTextBox1, 0, -20, 5000)
    End If
End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Me.ToolTip1.IsBalloon = True
    Me.MaskedTextBox1.Mask = "00/00/0000"
End Sub

Private Sub MaskedTextBox1_KeyDown(ByVal sender As Object, ByVal e As KeyEventArgs) Handles MaskedTextBox1.KeyDown
    ' The balloon tip is visible for five seconds; if the user types any data before it disappears, collapse it ourselves.
    Me.ToolTip1.Hide(Me.MaskedTextBox1)
End Sub

Answer 2

这取决于您编辑字符串的方式。无论如何，这正是你想要的：

     Private Sub TextBox1_KeyUp(sender As Object, e As KeyEventArgs) Handles TextBox1.KeyUp
    If TextBox1.Text.Length = 3 And e.KeyCode <> Keys.Back Then
        TextBox1.Text = TextBox1.Text.Insert(3, "-")
        TextBox1.SelectionStart = TextBox1.TextLength
    End If
End Sub

我想在前3个字符上添加Hypen

2 个答案: