Question

这可以检查吗？我无法在MSDN或其他任何地方找到太多帮助。我没有多少if / elses来检查数字是否输入到我的文本框中，我想把它全部放在一个数组或列表中，并根据输入的内容进行简单的包含（不存在）。如果在文本框内输入任何数字，我想要它只是删除文本框中突出显示的空文本。

 Private Sub txt_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles fptSSN.KeyPress
        Dim i As Integer
        Dim keysList As List(Of Keys)
        Dim keys() As Keys = {Windows.Forms.Keys.D0, Windows.Forms.Keys.D1, Windows.Forms.Keys.D2, Windows.Forms.Keys.D3, Windows.Forms.Keys.D4, Windows.Forms.Keys.D5, Windows.Forms.Keys.D6, Windows.Forms.Keys.D7, Windows.Forms.Keys.D8, Windows.Forms.Keys.D9, Windows.Forms.Keys.NumPad0, Windows.Forms.Keys.NumPad1, Windows.Forms.Keys.NumPad2, Windows.Forms.Keys.NumPad3, Windows.Forms.Keys.NumPad4, Windows.Forms.Keys.NumPad5, Windows.Forms.Keys.NumPad6, Windows.Forms.Keys.NumPad7, Windows.Forms.Keys.NumPad8, Windows.Forms.Keys.NumPad9}

        keysList.AddRange(keys)

           If txt.Text = "         " And e.KeyChar = ?????????????? Then
                txt.Text = ""
            End If
        Next
    End Sub

Answer 1

由于您正在寻找数字，您可以利用IsNumeric（）函数：

    If IsNumeric(e.KeyChar) Then
        txt.Text = String.Empty
        e.Handled = True
    End If

如果您不想在清除它时将数字放在文本框中，请设置e.Handled = True。

Answer 2

您可以使用Any：

Private Sub txt_KeyPress(ByVal sender As System.Object,
                        ByVal e As System.Windows.Forms.KeyPressEventArgs) _
                        Handles fptSSN.KeyPress

    Dim keysList As New List(Of Keys)(New Keys() _
    {
        Windows.Forms.Keys.D0, Windows.Forms.Keys.D1, Windows.Forms.Keys.D2,
        Windows.Forms.Keys.D3, Windows.Forms.Keys.D4, Windows.Forms.Keys.D5,
        Windows.Forms.Keys.D6, Windows.Forms.Keys.D7, Windows.Forms.Keys.D8,
        Windows.Forms.Keys.D9, Windows.Forms.Keys.NumPad0,
        Windows.Forms.Keys.NumPad1, Windows.Forms.Keys.NumPad2,
        Windows.Forms.Keys.NumPad3, Windows.Forms.Keys.NumPad4,
        Windows.Forms.Keys.NumPad5, Windows.Forms.Keys.NumPad6,
        Windows.Forms.Keys.NumPad7, Windows.Forms.Keys.NumPad8,
        Windows.Forms.Keys.NumPad9
    })

    If keysList.Any(Function(key) key.Equals(e.KeyChar)) AndAlso txt.Text = "         " Then
        txt.Text = ""
    End If

End Sub

检查e.KeyChar对一组键

2 个答案: