IP地址输入控件 V1.0.1.1版(FOR Win Form)

'只允许输入数字、"."     Private Sub txtField_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txtField0.KeyPress, txtField1.KeyPress, txtField2.KeyPress, txtField3.KeyPress         If e.KeyChar = "." Then             Dim tx As TextBox = CType(sender, TextBox)             '最后的文本框不可以输入"."             '在其它文本框输入"."，相当于输入"Tab"键，即光标到下一文本框             If tx.Text = "" Or tx.SelectedText <> "" Then                 e.Handled = True             End If             If tx.Name <> "txtField3" Then                 SendKeys.Send("{TAB}")             Else                 '最后的文本框不可以输入"."                 e.Handled = True             End If         ElseIf (Not IsNumeric(e.KeyChar)) And e.KeyChar <> ControlChars.Back Then             e.Handled = True         Else             Dim tx As TextBox = CType(sender, TextBox)             If (Len(tx.Text) = 2 And e.KeyChar <> ControlChars.Back And tx.SelectedText.Length = 0) Then                 If tx.Name <> "txtField3" Then                     SendKeys.Send("{TAB}")                 End If             End If         End If         '控制ControlChars.Back退格键         Dim tx1 As TextBox = CType(sender, TextBox)         If (Len(tx1.Text) = 0 And e.KeyChar = ControlChars.Back) Then             Select Case tx1.Name                 Case "txtField3"                     If txtField3.Text = "" Then                         txtField2.Focus()                     End If                 Case "txtField2"                     If txtField2.Text = "" Then                         txtField1.Focus()                     End If                 Case "txtField1"                     If txtField1.Text = "" Then                         txtField0.Focus()                     End If             End Select         End If     End Sub

转载于:https://www.cnblogs.com/mari/archive/2004/12/21/79843.html