if ($something) {
  print ExcelFmt('dd/mm/yyyy hh:mm', $eSheet->{Cells}[$row][$column]->
+unformatted()) . ","
} else {
  print $eSheet->{Cells}[$row][$column]->Value . ",";
}
[download]

I modified code as below and got error as

Global symbol "$cell" requires explicit package name at ./perl_excel_xls2n.pl line 28. Global symbol "$cell" requires explicit package name at ./perl_excel_xls2n.pl line 28. Global symbol "$value" requires explicit package name at ./perl_excel_xls2n.pl line 30. Global symbol "$cell" requires explicit package name at ./perl_excel_xls2n.pl line 30. Execution of ./perl_excel_xls2n.pl aborted due to compilation errors.

#!/usr/bin/perl -w
# For each tab (worksheet) in a file (workbook),
# spit out columns separated by ",",
# and rows separated by c/r.

use Spreadsheet::ParseExcel::Utility qw(ExcelFmt);

use strict;
my $file='output2.csv';
my $datefmt = 'dd/mm/yyyy';    # ISO 8601

open STDOUT, ">", $file or die "$0: open: $!";
open STDERR, ">&STDOUT"        or die "$0: dup: $!";

my $filename = shift || "/home/etc/srcfile.xls";
my $e = new Spreadsheet::ParseExcel;
my $eBook = $e->Parse($filename);
my $sheets = $eBook->{SheetCount};
my ($eSheet, $sheetName);

foreach my $sheet (0 .. $sheets - 1) {
    $eSheet = $eBook->{Worksheet}[$sheet];
    $sheetName = $eSheet->{Name};
    #print "#Worksheet $sheet: $sheetName\n";
    next unless (exists ($eSheet->{MaxRow}) and (exists ($eSheet->{Max
+Col})));
    foreach my $row ($eSheet->{MinRow} .. $eSheet->{MaxRow}) {
        foreach my $column ($eSheet->{MinCol} .. $eSheet->{MaxCol}) {
           if (defined $cell->{Type} && $cell->{Type} eq 'Date')
            {
               $value = ExcelFmt($datefmt, $cell->{Val});
            }
            if (defined $eSheet->{Cells}[$row][$column])
            {
                print $eSheet->{Cells}[$row][$column]->Value . ",";
            } else {
                print ",";
            }
        }
        print "\n";
    }
}
[download]

With use strict; you have to define variables before using them. That's what these mesages mean, you're using $cell and $value without having defined them.

Try

foreach my $sheet (0 .. $sheets - 1) {
  $eSheet = $eBook->{Worksheet}[$sheet];
  $sheetName = $eSheet->{Name};
  #print "#Worksheet $sheet: $sheetName\n";
  next unless (exists ($eSheet->{MaxRow}) and (exists ($eSheet->{MaxCo
+l})));
  foreach my $row ($eSheet->{MinRow} .. $eSheet->{MaxRow}) {
    foreach my $column ($eSheet->{MinCol} .. $eSheet->{MaxCol}) {
        
      my $cell = $eSheet->{Cells}[$row][$column];
      if (defined $cell){
        if (defined $cell->{Type} && $cell->{Type} eq 'Date'){
          print ExcelFmt($datefmt, $cell->unformatted() ) . ",";
        } else {
          print $cell->value() . ",";
        }
      } else {
        print ",";
      } 
    }
    print "\n";
  }
}
[download]

poj