When using XML::Simple, it's usually very helpful to use something like Data::Dumper to help understand the structure of the data. From my personal experience, attributes are usually hash keys and multiple tags at a level are usually arrays.

Here's the code that I came up with to parse your XML data and run it through Data::Dumper.

use strict;
use warnings;

use XML::Simple;
use Data::Dumper;

my $file = "data.xml";

my $xml = XMLin($file);

print Dumper($xml);

[download]

And here's the output.

$VAR1 = {
          'levels' => {
                      'level' => {
                                 'c' => {
                                        'target' => '22.1',
                                        'level' => {
                                                   'g' => {
                                                          'weight' => 
+'30.8',
                                                          'study' => {
                                                                     '
+p' => {
                                                                      
+      'weight' => '75',
                                                                      
+      'id' => '50'
                                                                      
+    },
                                                                     '
+q' => {
                                                                      
+      'weight' => '25',
                                                                      
+      'id' => '70'
                                                                      
+    }
                                                                   }
                                                        },
                                                   'd' => {
                                                          'level' => {
                                                                     '
+e' => {
                                                                      
+      'weight' => '44.4',
                                                                      
+      'study' => {
                                                                      
+                 'l' => {
                                                                      
+                        'weight' => '50',
                                                                      
+                        'id' => '34'
                                                                      
+                      },
                                                                      
+                 'm' => {
                                                                      
+                        'weight' => '50',
                                                                      
+                        'id' => '27'
                                                                      
+                      }
                                                                      
+               }
                                                                      
+    },
                                                                     '
+f' => {
                                                                      
+      'weight' => '55.6',
                                                                      
+      'study' => {
                                                                      
+                 'n' => {
                                                                      
+                        'weight' => '60',
                                                                      
+                        'id' => '25'
                                                                      
+                      },
                                                                      
+                 'o' => {
                                                                      
+                        'weight' => '40',
                                                                      
+                        'id' => '38'
                                                                      
+                      }
                                                                      
+               }
                                                                      
+    }
                                                                   },
                                                          'weight' => 
+'69.2'
                                                        }
                                                 },
                                        'weight' => '13'
                                      },
                                 'h' => {
                                        'target' => '19.0',
                                        'weight' => '22',
                                        'study' => {
                                                   'r' => {
                                                          'weight' => 
+'90.9',
                                                          'id' => '40'
                                                        },
                                                   's' => {
                                                          'weight' => 
+'9.1',
                                                          'id' => '22'
                                                        }
                                                 }
                                      },
                                 'b' => {
                                        'target' => '35.1',
                                        'weight' => '50',
                                        'study' => {
                                                   'j' => {
                                                          'weight' => 
+'70',
                                                          'id' => '36'
                                                        },
                                                   'i' => {
                                                          'weight' => 
+'30',
                                                          'id' => '32'
                                                        }
                                                 }
                                      }
                               },
                      'target' => '29.6',
                      'name' => 'a',
                      'study' => {
                                 'weight' => '15',
                                 'name' => 'k',
                                 'id' => '37'
                               }
                    },
          'study' => {
                     'u' => {
                            'spec' => 'p0f7=1',
                            'weight' => '0',
                            'id' => '19'
                          },
                     'v' => {
                            'weight' => '0',
                            'id' => '62'
                          },
                     't' => {
                            'spec' => 'p0f7=2',
                            'weight' => '0',
                            'id' => '19'
                          }
                   }
        };

[download]

That output should help you figure out how to write your code to traverse the data structure. If that's not a data structure that you're liking, you can check out the available options for the XMLin function or you might need to check out other XML parsing modules. Since I personally have only used XML::Simple, I can't really recommend any other modules to try.

In reply to Re: parsing multi level XML with XML::Simple by dasgar
in thread parsing multi level XML with XML::Simple by lcheung

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