Dim pattern As String = "^[0-9]{4,9}|1000000000$" Dim txt As String= "1000000000" Dim rgx = new System.Text.RegularExpressions.Regex(pattern, System.Text.RegularExpressions.RegexOptions.IgnoreCase) If rgx.isMatch(txt) = False Then msgbox("请输入正确的编号!") Return "" End If