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if string is numeric and 11 digits long

gerble1000
User

Jul 18, 2012, 3:53 AM

Post #1 of 5 (708 views)

if string is numeric and 11 digits long	Can't Post

could sombody help me with this please.
i need to check if $string is all numeric and if 11 digits long and starts with 07 else do other

examples would be
07232343576
07569898665
0946nd769
gciasu8neeeo

i need a simple if else statement

BillKSmith
Veteran

Jul 18, 2012, 4:33 AM

Post #2 of 5 (705 views)

Re: [gerble1000] if string is numeric and 11 digits long [In reply to]	Can't Post

If you are sure that $string contains what you think, use a regular expression. But be warned, if perl changes the numeric string to a number, the leading 0 is lost.

Code

   
 
use strict; 
use warnings; 
my @strings = ( 
    '07232343576', 
    '07569898665', 
    '0946nd769', 
    'gciasu8neeeo', 
); 
foreach my $string (@strings) { 
    if ($string =~ /07\d{9}/) { 
        print "valid: $string\n"; 
    } 
    else { 
        print "invalid $string\n"; 
    } 
}

Good Luck,
Bill

gerble1000
User

Jul 18, 2012, 5:48 AM

Post #3 of 5 (701 views)

Re: [BillKSmith] if string is numeric and 11 digits long [In reply to]	Can't Post

that worked great thanyou, could you explain why it works.
just need a breakdown like y is there a 9 and what does the 'd' do

BillKSmith
Veteran

Jul 18, 2012, 6:22 AM

Post #4 of 5 (696 views)

Re: [gerble1000] if string is numeric and 11 digits long [In reply to]	Can't Post

\d is a 'character class' which means match any decimal digit.

{9} is a 'quantifier' which means use 9 of the previous item (any digit). The 9 comes from eleven digits minus the two (07) already matched.

I forgot the anchors. The RE that I posted would match the specified pattern anywhere within a longer string. It should be:

Code

  
 
    if ($string =~ /^07\d{9}$/) {

Good Luck,
Bill

gerble1000
User

Jul 18, 2012, 8:11 AM

Post #5 of 5 (687 views)

Re: [BillKSmith] if string is numeric and 11 digits long [In reply to]	Can't Post

ideal thankyou bill

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