'========================================
' NUMERIC INPUT - NUMBERS ONLY 
' by cundo Liberty Basic Conforums
' Re: textbox input - numbers only
' Reply #10 on 23 April 2016 at 6:15pm
'========================================
' Modification to Symbols$ removes "-"
' from the exclusion list.  This allows
' negative numbers to be included.
'----------------------------------------
' The function num$(d$)has been included
' for LBB which does not recognise
' remchar$.  The function num$(d$) is a 
' modification of the routine provide in
' Liberty Basic Conforums by GaRPMorE in
' Reply #6 on: Apr 22nd, 2016, 7:23pm 
'========================================

nomainwin

textbox #main.textbox, 10, 50, 100, 25
WindowWidth = 350
WindowHeight = 150

open "Filtered Numeric Input" for window as #main
#main.textbox "!contents? txt$"
#main "trapclose [quit]"


[CheckInput]
timer 0

    #main.textbox "!contents? txt$"
    Symbols$ = "abcdefghijklmnopqrstuvwxyz";_
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ<>,:;!@#$%^&*()_=+`~"
    oldtxt$=txt$
    'txt$ = remchar$(  txt$ , Symbols$)
    txt$ = num$(txt$)   'replacement for remchar$()
    if oldtxt$<> txt$ then
        #main.textbox txt$
        handle = hWnd(#main.textbox)
        pos = len(txt$)
        calldll #user32, "SendMessageA", _
            handle as ulong, _
            _EM_SETSEL as long, _
            pos as long, _
            pos as long, _
            result as void
    end if

timer 300, [CheckInput]

wait


function num$(d$)
    for i=1 to len(d$)
        a=asc(mid$(d$,i,1))
        if a = 45 or a = 46 or a>47 and a<58 then num$=num$+chr$(a)
    next
end function

[quit]

close #main
end