Item Description: Manipulation routines for comma-separated values

Review Synopsis:

Author: Alan Citterman

I had a project where I needed to extract data from a file and send
it to a customer. The file in question was from a database, and it
had been exported to a CSV text file.

I would have tried to write my own regular expression to handle this,
but my overall knowledge of Perl isn't that good. However, after some
research, I found a reference to this module.

#!/usr/bin/perl
use strict;
use Text::CSV;
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I knew that the text file had lines of data that I didn't need, and
that there was an easily recognizable pattern in those lines, so I could
use a regular expression to put those lines into a trash file.

my $input="input.csv";
my $output="output.txt";
my $trash="trashfile";
my $csv=Text::CSV->new();     #Creates a new Text::CSV object

open(INFILE,$input) || die "Can't open file $input";
open(OUTFILE,">$output") || die "Can't open file $output";
open(TRASH,">$trash") || die "Can't open file $trash";
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Now to start reading the data from the file, store it in the $_ variable
and print it to the trash file if its not good, or parse the variable, and
print it to the output file if it is.

while (<INFILE>) {
if (/"X"/) {   #The trash data has these 3 characters in it
  print TRASH "$_\n";
}
else {  #Now to deal with the data I want to keep
  if($csv->parse($_)) {       #checks to see if data exists in $_ and 
+parses it if it does
    my @fields=$csv->fields;  # puts the values from each field in an 
+array
    my $elements=@fields;     #gets the number of elements in the arra
+y
    for ($x=0;$x<$elements;$x++) {
      print OUTFILE "$fields[$x]\t";
    }
  }
}
}
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Now that the files have been written to, I can close them up, and remove
the trash file

close INFILE;
close OUTFILE;
close TRASH;

unlink $trash;
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All in all, a very useful module.