各位大侠，text内怎么只能输入数字？

[stonea168]

各位大侠，text内怎么只能输入数字？谢谢

[stonea168]

我是这样做的
For i = 0 To TextBox1.Text.Length
TextBox1.SelectionStart = i
TextBox1.SelectionLength = i + 1

If TextBox1.Text = Nothing Then
MessageBox.Show("请输入数字", "warning")
Return
End If


j = Asc(TextBox1.Text)

If j < 48 Or j > 57 Then
MessageBox.Show("请输入数字", "warning")
TextBox1.Clear()
Return
End If

Next

但是输入前边是数字后边是字符的话 就会出错,,
之样做是不是很笨
有没有更好的解决办法,

[SqlDataAdapter]

最简单的方法:
Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
If Not (IsNumeric(e.KeyChar) Or e.KeyChar = Microsoft.VisualBasic.ChrW(8) Or e.KeyChar = Microsoft.VisualBasic.ChrW(46)) Then
e.Handled = True
End If
End Sub

[block]

单纯数字好办，问题是有些工程上记数就比较麻烦了，比如1.2e-12.5

[citylamp]

不用这么麻烦，正则表达式就ok了
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
If Regex.IsMatch(TextBox3.Text, "^[\d|+|-]\d+[.]\d$") Then
MsgBox("OK!!")
Else
TextBox3.Text = ""
End If
End Sub

[NoReady]

在文本框的keyPress事件中：

If Asc(e.KeyChar) > 26 Then
If (Asc(e.KeyChar) < Keys.D0 Or Asc(e.KeyChar) > Keys.D9) Then
e.Handled = True
Else
e.Handled = False
End If
End If

[Dugu_Niu]

最好做一个用户控件，以便以后重复使用，
从TextBox继承
在KeyPress事件中写以下代码:
Dim KeyAscii As Integer
KeyAscii = Asc(e.KeyChar)

Select Case KeyAscii

Case 48 To 57, 8, 13 ' these are the digits 0-9, backspace,
' and carriage return
' we're OK on these, don't do anything

Case 45 ' minus sign

' if we already have one, throw it away
If InStr(Me.Text, "-") <> 0 Then
KeyAscii = 0
Exit Sub
End If

' if the insertion point is not sitting at zero
' (which is beginning of field), throw away the minus
' sign (because it's not valid except in first position)
If Me.SelectionStart <> 0 Then
KeyAscii = 0
End If

Case 46 ' this is a period (decimal point)

' if we already have a period, throw it away
If InStr(Me.Text, ".") <> 0 Then
KeyAscii = 0
End If

Case Else
' provide no handling for the other keys
KeyAscii = 0

End Select

' If we want to throw the keystroke away, then set the event
' as already handled. Otherwise, let the keystroke be handled normally.
If KeyAscii = 0 Then
e.Handled = True
Else
e.Handled = False
End If

[Dugu_Niu]

接上文
做好之后编译生成dll文件，然后在你的项目中引用这个dll就可以

[stonea168]

thank you very much!!!!!!

[boxzang]

重载textbox的keypress事件,在里面输入以下代码
If Not Char.IsDigit(e.KeyChar) Then
e.Handled = True
Else
e.Handled = False
End If

[menuvb]

主 题： 屏蔽输入的字符
作 者： fenghuaxueyue (雪月)
信 誉 值： 95
所属论坛： .NET技术 VB.NET
问题点数： 10
回复次数： 1
发表时间： 2002-9-6 10:44:19




在VB。NET里我想在TEXTBOX 里只输入数字。把输入其他的字符屏蔽掉，请问怎么做！

帮帮忙！


回复人： Latitude(Henry) ( ) 信誉：98 2002-9-6 11:24:51 得分:10


Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress

'8-BACKSPACE回删

'46-"."

'你可以补充写else作输入的处理

If Not (IsNumeric(e.KeyChar) Or e.KeyChar = Microsoft.VisualBasic.ChrW(8) Or e.KeyChar = Microsoft.VisualBasic.ChrW(46)) Then

e.Handled = True '表示已处理完，即不显示了

End If

End Sub