); # LOOP THROUGH IT while (($key, $value) = each(%capitals)){ print $key.", ".$value."\n"; } 输出 Australia, Canberra India, New Delhi USA, Washington, D.C. South Korea, Seoul Perl按键排序哈希 你可以使用其键元素或值元素对哈希进行排序。 Perl为此提供了sort()函数。在此示例中, ...
# Loop through all the threads foreach my $thr (threads->list()) { $thr->join(); } If some threads have not finished running when the main Perl thread ends, Perl will warn you about it and die, since it is impossible for Perl to clean up itself while other threads are running. ...
$#arrayname is equivalent to scalar(@arrayname)-1. This is often used in foreach loops where you loop through an array by its index number:my @colors = ("cyan", "magenta", "yellow", "black"); foreach my $i (0..$#colors) { print "color $i is $colors[$i]\n"; } This ...
foreach $item ( in-some-array ) { do something with $item } Each time through the loop, the value of the $item variable is assigned to the next item in the array. When you've processed all the items in the array, the loop is done. Here's an example similar to the until and ...
rather than to loop through the entire array usinggrep()for instance.substr()may be (a lot) faster thangrep()but not as flexible, so you have another trade-off to access. Your code may contain a line which takes 0.01 of a second to execute which if you call it 1,000 times, quite...
If you are searching for an element in a list, it can be more efficient to store the data in a hash structure, and then simply look to see whether the key is defined, rather than to loop through the entire array using grep() for instance. substr() may be (a lot) faster than ...
Perl'skeys()function is used to iterate (loop) through the the keys of aHASH. The keys are returned as a list (array). %contact = ('name' => 'Bob', 'phone' => '111-111-1111'); foreach $key (keys %contact) { print "$key\n"; ...
time I may only need a single barcode dataset, the next time I might need 10. Rather than hardocding for a fixed number, and then all the extensive code to handle that number, what would be a way to get this all into a single variable or reference that I can just loop through?
Multiple files can be removed at once if we first create an array of files to be deleted and then loop through each one. There are several ways to go about this process.PERL Code: #!/usr/bin/perl print "content-type: text/html \n\n"; #The header @files = ("newtext.txt","more...
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