如何迭代哈希数组中的哈希数组

Question

关于迭代哈希数组的大量线程,我每天都这样做.但是现在我想迭代AoH和AoH.我对数组"章节"感兴趣,因为我想为该内部数组的每个数组元素添加一个哈希:

$criteria = [
    {
      'title' => 'Focus on Learning',
      'chapters' => [
                          {
                            'content_id' => '182',
                            'criteria_id' => '1',
                            'title' => 'Focus on Learning',
                          },
                          {
                            'content_id' => '185',
                            'criteria_id' => '1',
                            'title' => 'Teachers Role',
                          },
                          {
                            'content_id' => '184',
                            'criteria_id' => '1',
                            'title' => 'Parents in Class',
                          },
                          {
                            'content_id' => '183',
                            'criteria_id' => '1',
                            'title' => 'Students at Home',
                          }
                        ],
      'tot_chaps' => '4'
    },

从理论上讲,这是我想要的.

for my $i ( 0 .. $#$criteria ) {
   for my $j ( 0 .. $#$criteria->[$i]{'chapters'}) {
      print $criteria->[$i]{'chapters'}->[$j]{'title'}."\n";
   }
}

print $criteria->[$i]{'chapters'}->[1]{'title'}."\n"; -> Teachers Role

Answer 1

use warnings;
use strict;

foreach my $criterion (@$criteria) {
  foreach my $chapter (@{$criterion->{chapters}}) {
    print $chapter->{title}, "\n";
  }
}