check string rep's integer

[sinister]

Is there a PHP function to verify that a string validly represents an
integer?

[Alvaro G Vicario]

Re: check string rep's integer

*** sinister wrote/escribió (Fri, 21 Nov 2003 15:10:16 GMT):[color=blue]
> Is there a PHP function to verify that a string validly represents an
> integer?[/color]

Check is_int() manual page.

--
--
-- Álvaro G. Vicario - Burgos, Spain
--

[Michael Fuhr]

Re: check string rep's integer

"sinister" <sinister@nospa m.invalid> writes:
[color=blue]
> Is there a PHP function to verify that a string validly represents an
> integer?[/color]

See the Variable Functions chapter in the PHP manual:

http://www.php.net/manual/en/ref.variables.php

The answer may not be as simple as you'd initially think, so be
sure to read a function's description and user-contributed notes
before using it. Test whatever code you end up writing to make
sure it gives the expected results for both integers and non-integers.

You could also use a regular expression, but using variable functions
would probably make your intentions more clear.

--
Michael Fuhr

http://www.fuhr.org/~mfuhr/

[sinister]

Re: check string rep's integer


"Alvaro G Vicario" <alvaro_QUITAR_ REMOVE@telecomp uteronline.com> wrote in
message news:1pg01rztod ora.12za8gcvf9h nq.dlg@40tude.n et...[color=blue]
> *** sinister wrote/escribió (Fri, 21 Nov 2003 15:10:16 GMT):[color=green]
> > Is there a PHP function to verify that a string validly represents an
> > integer?[/color]
>
> Check is_int() manual page.[/color]

No; that checks whether a variable is an integer, not whether a string
variable corrected represents an integer.

I'm thinking of
"66" true
"00037" true
"afdfdfd" false
"-00218" true
"- 18" false
[color=blue]
>
> --
> --
> -- Álvaro G. Vicario - Burgos, Spain
> --[/color]

[sinister]

Re: check string rep's integer


"Michael Fuhr" <mfuhr@fuhr.org > wrote in message
news:3fbe32d3_1 @omega.dimensio nal.com...[color=blue]
> "sinister" <sinister@nospa m.invalid> writes:
>[color=green]
> > Is there a PHP function to verify that a string validly represents an
> > integer?[/color]
>
> See the Variable Functions chapter in the PHP manual:
>
> http://www.php.net/manual/en/ref.variables.php[/color]

Not sure I understand the connection to variable functions. I would have
thought that I need a function on a string, returning a boolean, and that
either (a) it's already in php, or (b) I'd have to write my own.

I've done (b) in C and C++.
[color=blue]
> The answer may not be as simple as you'd initially think, so be
> sure to read a function's description and user-contributed notes
> before using it. Test whatever code you end up writing to make
> sure it gives the expected results for both integers and non-integers.
>
> You could also use a regular expression, but using variable functions
> would probably make your intentions more clear.
>
> --
> Michael Fuhr
> http://www.fuhr.org/~mfuhr/[/color]

[Michael Fuhr]

Re: check string rep's integer

"sinister" <sinister@nospa m.invalid> writes:
[color=blue]
> "Michael Fuhr" <mfuhr@fuhr.org > wrote in message
> news:3fbe32d3_1 @omega.dimensio nal.com...[color=green]
> > "sinister" <sinister@nospa m.invalid> writes:
> >[color=darkred]
> > > Is there a PHP function to verify that a string validly represents an
> > > integer?[/color]
> >
> > See the Variable Functions chapter in the PHP manual:
> >
> > http://www.php.net/manual/en/ref.variables.php[/color]
>
> Not sure I understand the connection to variable functions. I would have
> thought that I need a function on a string, returning a boolean, and that
> either (a) it's already in php, or (b) I'd have to write my own.[/color]

Did you look at the list of functions at the above link? If none
of them seem suitable, could you explain why? As I mentioned in
my first followup, the solution isn't as obvious as it might seem
at first, but it's there if you read the documentation and user
comments.

--
Michael Fuhr

http://www.fuhr.org/~mfuhr/

[sinister]

Re: check string rep's integer


"Michael Fuhr" <mfuhr@fuhr.org > wrote in message
news:3fbebd84$1 _2@omega.dimens ional.com...[color=blue]
> "sinister" <sinister@nospa m.invalid> writes:
>[color=green]
> > "Michael Fuhr" <mfuhr@fuhr.org > wrote in message
> > news:3fbe32d3_1 @omega.dimensio nal.com...[color=darkred]
> > > "sinister" <sinister@nospa m.invalid> writes:
> > >
> > > > Is there a PHP function to verify that a string validly represents[/color][/color][/color]
an[color=blue][color=green][color=darkred]
> > > > integer?
> > >
> > > See the Variable Functions chapter in the PHP manual:
> > >
> > > http://www.php.net/manual/en/ref.variables.php[/color]
> >
> > Not sure I understand the connection to variable functions. I would[/color][/color]
have[color=blue][color=green]
> > thought that I need a function on a string, returning a boolean, and[/color][/color]
that[color=blue][color=green]
> > either (a) it's already in php, or (b) I'd have to write my own.[/color]
>
> Did you look at the list of functions at the above link? If none
> of them seem suitable, could you explain why? As I mentioned in[/color]

OK, looking at the page again, I see what you mean. Basically, it's (b)
"I'd have to write my own," but the user comments show how to make it short
and sweet.

Thanks.

Best,

S
[color=blue]
> my first followup, the solution isn't as obvious as it might seem
> at first, but it's there if you read the documentation and user
> comments.
>
> --
> Michael Fuhr
> http://www.fuhr.org/~mfuhr/[/color]

[Alvaro G Vicario]

Re: check string rep's integer

*** sinister wrote/escribió (Fri, 21 Nov 2003 20:14:29 GMT):[color=blue][color=green]
>> Check is_int() manual page.[/color]
>
> No; that checks whether a variable is an integer, not whether a string
> variable corrected represents an integer.[/color]

You are right. Probably intval() is a better choice.

--
--
-- Álvaro G. Vicario - Burgos, Spain
--