NetNews Usenet Archive 1992 #19/NN_1992_19.iso/spool/comp/lang/pascal/5052

Internet Message Format | 1992-08-25 | 1.8 KB

Path: sparky!uunet!spool.mu.edu!mixcom.com!ddxxdd
From: [e-mail] (Jeff Ding)
Newsgroups: comp.lang.pascal
Subject: Re: want to help me make my 'value' routine crash-proof?
Message-ID: <[e-mail]>
Date: 25 Aug 92 21:41:51 GMT
Article-I.D.: mixcom.1992Aug25.214151.3208
References: <[e-mail]>
Organization: Milwaukee Internet Xchange BBS, Milwaukee, WI U.S.A.
Lines: 61

In article <[e-mail]> [e-mail] writes:
>
>function value(I:string):word;
>var n:real; n1:integer;
> begin
> val(i,n,n1);
> if n1<>0 then begin
>  i:=copy(i,1,n1-1);
>  val(i,n,n1);
> end;
> value:=n;
> if i='' then value:=0;
> end;
>
>of course, when i pass a loaded string such as '99999' the routine crashes.
>maxing out at 65535 is desired.
>
>so what's the quick and dirty?
>

Here is my example String-To-Word conversion program.  It is quick, simple
and even converts negative numbers appropriately.  Any error will result
in the word equal to 0.  You can add an error flag very easily.


program TestValue;


var  S : string;
     V : word;


function StrToWord(S: string): word;

  var  N   : word;
       Err : integer;

  begin
    Val(S, N, Err);
    if Err > 0 then S:= Copy(S, 1, Err - 1);
    Val(S, N, Err);
    if (Length(S) < 7) and (S < '65536') then
      StrToWord:= N else StrToWord:= 0
  end;  {StrToWord}


begin
  write('Enter a number: ');
  readln(S);
  V:= StrToWord(S);
  writeln('The ''WORD'' value is: ',V);
end.


>--
>\clinkenpeel: aberrant analytical cynical agnostic idealist.  i exclusively /
>/represent myself.  i do not offend anyone; however, some morons choose to  \
>\offend themselves.  judge only those who you would have judge yourself.  i /
>/don't practice what i preach - i'm not the type of person i'm preaching to.\

[e-mail]