How do I delete a specific element from an XML file

Maxim has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks,
I am trying to remove a specific elements from an XML file. In my XML file I can have more than one the same element, example <channel>.I can delete the value with this delete $category->{'subcategory'}[$countersubs]{'product'}[$counterprod]{'channel'}[$counterchan] || die "Error";. When I try anohter way like delete $category->{'subcategory'}[$countersubs]{'product'}[$counterprod]{'channel'} || die "Error";, it delete all the elements. Where am I wrong??

Here the code


use strict;
use warnings;
use XML::Simple;
use CGI ':standard';
use Data::Dumper;

#Variable
my $countersubs = 0;
my $counterchan = 0;
my $subprod = 'asa';
my $counterprod = 0;

my $prodid = '3';
my $schan = 'j';

print header;

my $arrays = [qw/subcategory name packaging_qty receipe description pr
+oduct paragraph comments channel brand conditionning product_id headi
+ng photo/];

print "Test2\n";
my $category = XMLin(\*DATA, keyattr => 1, forcearray => $arrays) || d
+ie "can't open the file";


foreach my $subcategory (@{$category->{'subcategory'}}) 
{
    my $inssub = $category->{'subcategory'}[$countersubs]{'name'} || d
+ie "An error occur!";

    if ($inssub eq $subprod)
    {
        foreach my $product (@{$subcategory->{'product'}}) 
        {
            foreach my $product_id (@{$product->{'product_id'}}) 
            {
                if ($product_id eq $prodid) 
                {
                    foreach my $channel (@{$product->{'channel'}}) 
                    {
                        if ($channel eq $schan) 
                        {
                            delete $category->{'subcategory'}[$counter
+subs]{'product'}[$counterprod]{'channel'} || die "Error";
                            print XMLout($category, xmldecl => '<?xml 
+version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href
+="products.xsl"?>', rootname =>'category');
                
                            exit 1;

                        }

                        $counterchan++;

                    }
                 }

            }

            $counterprod++;
        }
    }

    $countersubs++;
}

__DATA__
<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl"
+ href="products.xsl"?>
<category name="Coffee">
  <subcategory name="loop">
    <comments>
      <paragraph>jk</paragraph>
    </comments>
    <product recipe="/recipes/coffee1333.html">Coffee<brand>d</brand>
      <channel>d</channel>
      <channel>g</channel>
      <conditionning unit="d">d</conditionning>
      <description>d</description>
      <packaging_qty>d</packaging_qty>
      <product_id>d</product_id>
    </product>
  </subcategory>
  <subcategory name="asa">
    <comments>
      <paragraph>dsfs</paragraph>
    </comments>
    <product recipe="/recipes/coffee1333.html">Coffee<brand>3</brand>
      <channel>j</channel>
      <channel>j</channel>
      <conditionning unit="3">3</conditionning>
      <description>3</description>
      <packaging_qty>3</packaging_qty>
      <product_id>3</product_id>
    </product>
  </subcategory>
</category>
</readmore>
[download]

Maxim

Comment on How do I delete a specific element from an XML file Select or Download Code

Replies are listed 'Best First'.
Re: How do I delete a specific element from an XML file by pg (Canon) on Oct 31, 2004 at 03:37 UTC
That's what supposed to happen. If you do a Data::Dumper of $category, you will see that `$category->{'subcategory'}[$countersubs]{'product'}[$counterprod]{'channel'}` is a hash element that contains an array ref. `delete $category->{'subcategory'}[$countersubs]{'product'}[$counterpro +d]{'channel'}[counterchan]` [download] deletes the counterchan th element of the array. (I think "counterchan" is a typo of "$counterchan") `delete $category->{'subcategory'}[$countersubs]{'product'}[$counterpro +d]{'channel'}` [download] deletes the hash element, which is the entire array.	[reply] [d/l] [select]
Re^2: How do I delete a specific element from an XML file by pg (Canon) on Oct 31, 2004 at 03:50 UTC
A side note: delete an array element does not shift index. Try the following example: `use Data::Dumper; use strict; use warnings; my @a = (1,2,3,4,5); print Dumper(\@a); delete $a[1]; #splice(@a, 1,1); print Dumper(\@a);` [download] It gives you: `$VAR1 = [ 1, 2, 3, 4, 5 ]; $VAR1 = [ 1, undef, 3, 4, 5 ];` [download] The array after deletion does not become something like `$VAR1 = [ 1, 3, 4, 5 ];` [download] as splice does.	[reply] [d/l] [select]
Re^3: How do I delete a specific element from an XML file by Maxim (Sexton) on Oct 31, 2004 at 05:18 UTC
Sorry about the spelling mistake I made for `$counterchan`. I understand in general what you said with the example but how do I implemented?	[reply] [d/l]
Re^3: How do I delete a specific element from an XML file by Maxim (Sexton) on Nov 02, 2004 at 04:02 UTC
I found the problem, it come from with the exit command. WIth this it works well `delete $category->{'subcategory'}[$countersubs]{'product'}[$counterpro +d]{'channel'}[$counterchan]` [download] only when all loops is finished their process.	[reply] [d/l]
Re^3: How do I delete a specific element from an XML file by Maxim (Sexton) on Nov 02, 2004 at 06:45 UTC
Probem solve! Just need to put the command "exit 1" outside of the loop with a condition and everything works welll. Example:`exit 1 if isDel;`	[reply] [d/l]