VB Text1输入限制问题?

Text1前面第1位这可以输入A D F J 这四个字母,不分大小写.
然后,后面这可以输入3数字.不得超出255

如:A001 ~ A255

判断那们格式输入是否出错

MsgBox "输入格式错误，请重新输入！", , "提示"
前面不能输入其它字母也要判断,出错...快
要限制字母的输入,这可以输入A,D,F,J 不分大小写.

private sub text1_change()
if len(text1.text)<4 then exit sub
select case ucase(left(text1.text,1))
case "A","D","F","J"
select case val(right(text1.text,3))
case 0 to 255
case else
MsgBox "输入格式错误，请重新输入！", , "提示"
end select
case else
MsgBox "输入格式错误，请重新输入！", , "提示"
end select
end sub

有错误么？？

baoshengzhu 的回答是正确的，当然你还可以全部用Ascii做检测 Asc() wAsc()（如果我没记错的话）

Private Sub Command1_Click() Select Case UCase(Left(Text1.Text, 1)) Case "A", "D", "F", "J" Select Case Val(Right(Text1.Text, 3)) Case 0 To 255 Case Else MsgBox "输入格式错误，请重新输入！", , "提示" End Select Case Else MsgBox "输入格式错误，请重新输入！", , "提示" End Select End Sub

private sub text1_keypress(keyascii as integer) '禁止输入非数字字符 if keyascii < 48 or keyascii > 57 then keyascii = 0 end if end sub private sub text1_keypress(keyascii as integer) '禁止输入非大写字符 if keyascii < 65 or keyascii > 90 then keyascii = 0 end if end sub private sub text1_keypress(keyascii as integer) '禁止输入非英文字母 if keyascii > 90 and keyascii > 97 or keyascii < 65 or keyascii > 122 then keyascii = 0 end if end sub