Perl XML到CSV解析

Question

I have been trying to figure out how to get an xml data source parsed into a CSV file and it's driving me a little crazy. I have a data source that I need to parse an create a CSV. I also need to be able to include the Node ID as a column. Here is what I have:

         #!/usr/bin/perl
            use warnings;
        use strict;
        use XML::XPath;

        #Name of the CSV File
        my $filename = "parse.csv";

        #Create the file.
        open(INPUT,">$filename") or die "Cannot create file";

        #Collect the XML and set nodes
        my($xp) = XML::XPath->new( join('', <DATA>) );
        my(@records) = $xp->findnodes( '/CATALOG/CD' );
        my($firstTime) = 0;

        #Loop through each record
        foreach my $record ( @records ) {
            my(@fields) = $xp->find( './child::*', $record )->get_nodelist();
            unless ( $firstTime++ ) {
            #Print Headers
                print( join( ',', map { $_->getName() } @fields ), "\n");
            }
            #Print Content
                print( join( ',', map { $_->string_value() } @fields ), "\n");
        }
        #Close the file.
        close(INPUT);


        __DATA__
        <FOOD>
            <ITEM id='1'>
                <Color>Brown</Color>
                <Name>Steak</Name>
            </ITEM>
            <ITEM id='2'>
                <Color>Blue</Color>
                <Name>Blueberries</Name>
            </ITEM>
            <ITEM id='3'>
                <Color>Red</Color>
                <Name>Apple</Name>
            </ITEM>
        </FOOD>

It creates a CSV but its empty & I think its because of the print lines in the foreach loop.

Any help would be greatly appreciated!

Answer 1

You are printing your headers and content to Standard Output, not to your output file. You need to pass the file handle as the first argument to print without a comma between it and what you want to print. Something like: print FILE join(',', ...), "\\n";

I would also recommend not using INPUT as the file handle you are outputting to - it makes it a little confusing to understand the code.

Answer 2

Given the simplicity of the XML schema, this easier to do with AnyData

For instance:

#!/usr/bin/perl
# This script converts a XML file to CSV format.

# Load the AnyData XML to CSV conversion modules
use XML::Parser;
use XML::Twig;
use AnyData;

my $input_xml = "test.xml";
my $output_csv = "test.csv";


$flags->{record_tag} = 'ITEM';
adConvert( 'XML', $input_xml, 'CSV', $output_csv, $flags );

Would convert your data structure (XML) into:

id,Color,Name
1,Brown,Steak
2,Blue,Blueberries
3,Red,Apple

Answer 3

In your case , you are using /CATALOG/CD rather than your data. Please use something like

my(@records) = $xp->findnodes( '/FOOD/ITEM' );
....
...
...
print INPUT ( join( ',', map { $_->getName() } @fields ), "\n" );