function CheckDigit(const Input: string): boolean;

[CurryWurst]

Script Name: CheckDigit
Script Description: CheckDigit() checks an Input for integer literals.
Original Author(s): Dual

Hosted by: http://soldatcentral.com/
Core Version:  2.6.3
Compile Test: Passed

Code: [Select]

function CheckDigit(const Input: string): boolean;
var
  i, len: integer;
  Ch: char;
begin
  len:= length(Input);
  for i:= 1 to len do
  begin
    Ch:= Input[i];
    if ((Ord(Ch) - 48 >= 0) and (Ord(Ch) - 48 <= 9)) then
    begin
      Result:= true;
      continue;
    end else
    begin
      if ((Ch = ' ') and (not(Result))) then
      begin
        continue;
      end else
      begin
        Result:= false;
        break;
      end;
    end;
  end;
end;

Parameters

Input: string
String to be checked (e.g. user input).

Return Value

The return value depends on the Input. On success CheckDigit() returns true and validates the string for converting it with StrToInt().

Note

CheckDigit() will also return true if you pass a string like '  5' because the input can be converted by StrToInt().

Update(s)

29/30-Oct-2008:

• minor code improvements

3-Aug-2008:

• added support for spaces

(Size 620 B)
- http://soldatcentral.com/index.php?page=script&f=56 -

[danmer]

nice... And i suppose it's faster than RegExpMatch('^[0-9]*$',input) ?

[CurryWurst]

Maybe it works faster

[DorkeyDear]

http://forums.soldat.pl/index.php?topic=27844 -- a method of timing it, fairly simple (although not always correct after an hour of waiting i think, if i remember correctly, but im sure your not testing for over an hour)

[CurryWurst]

Yea, your idea is great!
I will try it out some time.

[rhide]

To be honest are loops generally pretty slow, often slower than built in functions such as regexp. Also, you only test for 1-9, commas ans periods are also most often considered numeric. Dont forget spaces btw

[CurryWurst]

To be honest are loops generally pretty slow, often slower than built in functions such as regexp. Also, you only test for 1-9, commas ans periods are also most often considered numeric. Dont forget spaces btw

I'm wondering whether RegExpMatch uses loops too, but I'm almost sure ...  it makes use of them!?
To be honest I'm checking for 0-9 - try it out yourself , it works
Adding support for commas, spaces and periods are great suggestions for upcoming versions. I will think about it.

[SpiltCoffee]

RegExpMatch('^\d+$',Source) (or something along those lines) would work faster, IMO, as you'd only do one check opposed to a whole for loop for each character with your current method.

[CurryWurst]

During the development of CheckDigit I had never pursued the aim to create a function which works faster than RegExpMatch. I only try to offer people who are interested in soldat scripting another possibility to check a string for numeric characters. This script is supposed to address particularly people who aren't able to use RegExpMatch 

[CurryWurst]

UPDATE

• minor code improvements