how to get the number of keys in an hash

[Liang]

Hi,

I need to get the number of keys in an hash. Is there any convenient way to
get it?

or use the following one?
foreach $v (keys %hash){
$count++;
}

Thanks in advance,
Liang

[Jürgen Exner]

Re: how to get the number of keys in an hash

Liang wrote:[color=blue]
> Hi,
>
> I need to get the number of keys in an hash. Is there any convenient
> way to get it?
>
> or use the following one?
> foreach $v (keys %hash){
> $count++;
> }[/color]

Oh dear, that's a rather creative way....

Trivial. Just use "keys(%hash )" in scalar context, e.g.
my $number = keys %hash;

jue

[Jeff Dunn]

Re: how to get the number of keys in an hash

"Liang" <leo2002chen@ho tmail.com> wrote in message news:<cgh23l$sf 4$1@newshost.mo t.com>...[color=blue]
> Hi,
>
> I need to get the number of keys in an hash. Is there any convenient way to
> get it?
>
> or use the following one?
> foreach $v (keys %hash){
> $count++;
> }
>
> Thanks in advance,
> Liang[/color]


Try

$keyCount=(%key s %hash);

[nobull@mail.com]

Re: how to get the number of keys in an hash

"Liang" <leo2002chen@ho tmail.com> wrote in message news:<cgh23l$sf 4$1@newshost.mo t.com>...[color=blue]
> Hi,
>
> I need to get the number of keys in an hash. Is there any convenient way to
> get it?[/color]

Yes, the keys() function.
[color=blue]
> or use the following one?
> foreach $v (keys %hash){
> $count++;
> }[/color]

No, that is not necesary.

This newsgroup does not exist (see FAQ). Please do not start threads here.
[color=blue]
> Thanks in advance,[/color]

If you are going to do any things "in advance" then my suggestions would be:

1) Check the FAQ.
2) Check the documentation for the functions you are using.

[Steve Bennett]

Re: how to get the number of keys in an hash

Everyone says "See FAQ". Could you please include the URL to the FAQ?
Be kind to newbies......Yo u used to be one.

-s

nobull@mail.com wrote:[color=blue]
>
> "Liang" <leo2002chen@ho tmail.com> wrote in message news:<cgh23l$sf 4$1@newshost.mo t.com>...[color=green]
> > Hi,
> >
> > I need to get the number of keys in an hash. Is there any convenient way to
> > get it?[/color]
>
> Yes, the keys() function.
>[color=green]
> > or use the following one?
> > foreach $v (keys %hash){
> > $count++;
> > }[/color]
>
> No, that is not necesary.
>
> This newsgroup does not exist (see FAQ). Please do not start threads here.
>[color=green]
> > Thanks in advance,[/color]
>
> If you are going to do any things "in advance" then my suggestions would be:
>
> 1) Check the FAQ.
> 2) Check the documentation for the functions you are using.[/color]

[Joe Smith]

Re: how to get the number of keys in an hash

Steve Bennett wrote:
[color=blue]
> Everyone says "See FAQ". Could you please include the URL to the FAQ?[/color]

What happens when you do a Google search on "perl faq"?
Newbies are expected to know that Google is their friend.

[Jürgen Exner]

Re: how to get the number of keys in an hash

Steve Bennett wrote:[color=blue]
> Everyone says "See FAQ". Could you please include the URL to the FAQ?[/color]

No need for a URL, it's on your own harddrive (after you installed Perl)
Just type
perldoc perlfaq
[color=blue]
> Be kind to newbies......Yo u used to be one.[/color]

You also seem to be new to Usenet. It is considered rude to
- top post
- blindly full quote
For an explanation of what that is and why it's considered rude please
search www.google.com

jue

[nobull@mail.com]

Re: how to get the number of keys in an hash

Steve Bennett rudely spits TOFU in may face:
[color=blue]
> Everyone says "See FAQ". Could you please include the URL to the FAQ?[/color]

You are supposed to look for a FAQ _before_ you ask a question. It
would defeat the purpose if the FAQ was so hard to find that asking
where it was was a ligitimate question. Anything you could reasonably
imagine doing to locate the Perl FAQ will succede in about fifteen
seconds.
[color=blue]
> Be kind to newbies.[/color]

I am. Teaching newbies that selfishness is rewarded is _not_ a
kindness.