local-host 2009-06-10 09:56 采纳率: 100%
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在 foreach 循环中自动获取循环索引

If I have the following array in Perl:

@x = qw(a b c);

and I iterate over it with foreach, then $_ will refer to the current element in the array:

foreach (@x) {
    print;
}

will print:

abc

Is there a similar way to get the index of the current element, without manually updating a counter? Something such as:

foreach (@x) {
    print $index;
}

where $index is updated like $_ to yield the output:

012

转载于:https://stackoverflow.com/questions/974656/automatically-get-loop-index-in-foreach-loop-in-perl

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  • 北城已荒凉 2009-06-10 10:42
    关注

    Like codehead said, you'd have to iterate over the array indices instead of its elements. I prefer this variant over the C-style for loop:

    for my $i (0 .. $#x) {
        print "$i: $x[$i]\n";
    }
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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