Perl - empty rows while writing CSV from Excel - perl

Question

I want to convert excel-files to csv-files with Perl. For convenience I like to use the module File::Slurp for read/write operations. I need it in a subfunction.
While printing out to the screen, the program generates the desired output, the generated csv-files unfortunately just contain one row with semicolons, field are empty.
Here is the code:
#!/usr/bin/perl
use File::Copy;
use v5.14;
use Cwd;
use File::Slurp;
use Spreadsheet::ParseExcel;
sub xls2csv {
my $currentPath = getcwd();
my #files = <$currentPath/stage0/*.xls>;
for my $sourcename (#files) {
print "Now working on $sourcename\n";
my $outFile = $sourcename;
$outFile =~ s/xls/csv/g;
print "Output CSV-File: ".$outFile."\n";
my $source_excel = new Spreadsheet::ParseExcel;
my $source_book = $source_excel->Parse($sourcename)
or die "Could not open source Excel file $sourcename: $!";
foreach my $source_sheet_number ( 0 .. $source_book->{SheetCount} - 1 )
{
my $source_sheet = $source_book->{Worksheet}[$source_sheet_number];
next unless defined $source_sheet->{MaxRow};
next unless $source_sheet->{MinRow} <= $source_sheet->{MaxRow};
next unless defined $source_sheet->{MaxCol};
next unless $source_sheet->{MinCol} <= $source_sheet->{MaxCol};
foreach my $row_index (
$source_sheet->{MinRow} .. $source_sheet->{MaxRow} )
{
foreach my $col_index (
$source_sheet->{MinCol} .. $source_sheet->{MaxCol} )
{
my $source_cell =
$source_sheet->{Cells}[$row_index][$col_index];
if ($source_cell) {
print $source_cell->Value, ";"; # correct output!
write_file( $outFile, { binmode => ':utf8' }, $source_cell->Value, ";" ); # only one row of semicolons with empty fields!
}
}
print "\n";
}
}
}
}
xls2csv();
I know it has something to do with the parameter passing in the write_file function, but couldn't manage to fix it.
Has anybody an idea?
Thank you very much in advance.

Answer 1

write_file will overwrite the file unless the append => 1 option is given. So this:
write_file( $outFile, { binmode => ':utf8' }, $source_cell->Value, ";" );
Will write a new file for each new cell value. It does however not match your description of "only one row of semi-colons of empty fields", as it should only be one semi-colon, and one value.
I am doubtful towards this sentiment from you: "For convenience I like to use the module File::Slurp". While the print statement works as it should, using File::Slurp does not. So how is that convenient?
What you should do, if you still want to use write_file is to gather all the lines to print, and then print them all at once at the end of the loop. E.g.:
$line .= $source_cell->Value . ";"; # use concatenation to build the line
...
push #out, "$line\n"; # store in array
...
write_file(...., \#out); # print the array
Another simple option would be to use join, or to use the Text::CSV module.

Answer 2

Well, in this particular case, File::Slurp was indeed complicating this for me. I just wanted to avoid to repeat myself, which I did in the following clumsy working solution:
#!/usr/bin/perl
use warnings;
use strict;
use File::Copy;
use v5.14;
use Cwd;
use File::Basename;
use File::Slurp;
use Tie::File;
use Spreadsheet::ParseExcel;
use open qw/:std :utf8/;
# ... other functions
sub xls2csv {
my $currentPath = getcwd();
my #files = <$currentPath/stage0/*.xls>;
my $fh;
for my $sourcename (#files) {
say "Now working on $sourcename";
my $outFile = $sourcename;
$outFile =~ s/xls/csv/gi;
if ( -e $outFile ) {
unlink($outFile) or die "Error: $!";
print "Old $outFile deleted.";
}
my $source_excel = new Spreadsheet::ParseExcel;
my $source_book = $source_excel->Parse($sourcename)
or die "Could not open source Excel file $sourcename: $!";
foreach my $source_sheet_number ( 0 .. $source_book->{SheetCount} - 1 )
{
my $source_sheet = $source_book->{Worksheet}[$source_sheet_number];
next unless defined $source_sheet->{MaxRow};
next unless $source_sheet->{MinRow} <= $source_sheet->{MaxRow};
next unless defined $source_sheet->{MaxCol};
next unless $source_sheet->{MinCol} <= $source_sheet->{MaxCol};
foreach my $row_index (
$source_sheet->{MinRow} .. $source_sheet->{MaxRow} )
{
foreach my $col_index (
$source_sheet->{MinCol} .. $source_sheet->{MaxCol} )
{
my $source_cell =
$source_sheet->{Cells}[$row_index][$col_index];
if ($source_cell) {
print $source_cell->Value, ";";
open( $fh, '>>', $outFile ) or die "Error: $!";
print $fh $source_cell->Value, ";";
close $fh;
}
}
print "\n";
open( $fh, '>>', $outFile ) or die "Error: $!";
print $fh "\n";
close $fh;
}
}
}
}
xls2csv();
I'm actually NOT happy with it, since I'm opening and closing the files so often (I have many files with many lines). That's not very clever in terms of performance.
Currently I still don't know how to use the split or Text:CSV in this case, in order to put everything into an array and to open, write and close each file only once.
Thank you for your answer TLP.