NAME

Text::CSV_XS - comma-separated values manipulation routines

SYNOPSIS

 use Text::CSV_XS;

 $csv = Text::CSV_XS->new();           # create a new object
 $csv = Text::CSV_XS->new(\%attr);     # create a new object

 $status = $csv->combine(@columns);    # combine columns into a string
 $line = $csv->string();               # get the combined string

 $status = $csv->parse($line);         # parse a CSV string into fields
 @columns = $csv->fields();            # get the parsed fields

 $status = $csv->status();             # get the most recent status
 $bad_argument = $csv->error_input();  # get the most recent bad argument

 $status = $csv->print($io, $columns); # Write an array of fields immediately
                                       # to a file $io

 $columns = $csv->getline($io);        # Read a line from file $io, parse it
                                       # and return an array ref of fields

 $csv->types(\@t_array);               # Set column types

DESCRIPTION

Text::CSV_XS provides facilities for the composition and decomposition of comma-separated values. An instance of the Text::CSV_XS class can combine fields into a CSV string and parse a CSV string into fields.

FUNCTIONS

version()

(Class method) Returns the current module version.

new(\%attr)

(Class method) Returns a new instance of Text::CSV_XS. The objects attributes are described by the (optional) hash ref \%attr. Currently the following attributes are available:

quote_char

The char used for quoting fields containing blanks, by default the double quote character ("). A value of undef suppresses quote chars. (For simple cases only).

eol

An end-of-line string to add to rows, usually undef (nothing, default), "\012" (Line Feed) or "\015\012" (Carriage Return, Line Feed)

escape_char

The char used for escaping certain characters inside quoted fields, by default the same character. (")

sep_char

The char used for separating fields, by default a comme. (,)

binary

If this attribute is TRUE, you may use binary characters in quoted fields, including line feeds, carriage returns and NUL bytes. (The latter must be escaped as "0.) By default this feature is off.

types

A set of column types; this attribute is immediately passed to the types method below. You must not set this attribute otherwise, except for using the types method. For details see the description of the types method below.

always_quote

By default the generated fields are quoted only, if they need to, for example, if they contain the separator. If you set this attribute to a TRUE value, then all fields will be quoted. This is typically easier to handle in external applications. (Poor creatures who aren't using Text::CSV_XS. :-)

To sum it up,

 $csv = Text::CSV_XS->new();

is equivalent to

 $csv = Text::CSV_XS->new({
     'quote_char'  => '"',
     'escape_char' => '"',
     'sep_char'    => ',',
     'binary'      => 0
 });

combine

 $status = $csv->combine(@columns);

This object function constructs a CSV string from the arguments, returning success or failure. Failure can result from lack of arguments or an argument containing an invalid character. Upon success, string() can be called to retrieve the resultant CSV string. Upon failure, the value returned by string() is undefined and error_input() can be called to retrieve an invalid argument.

print

 $status = $csv->print($io, $columns);

Similar to combine, but it expects an array ref as input (not an array!) and the resulting string is not really created, but immediately written to the $io object, typically an IO handle or any other object that offers a print method. Note, this implies that the following is wrong:

 open(FILE, ">whatever");
 $status = $csv->print(\*FILE, $columns);

The glob \*FILE is not an object, thus it doesn't have a print method. The solution is to use an IO::File object or to hide the glob behind an IO::Wrap object. See IO::File(3) and IO::Wrap(3) for details.

For performance reasons the print method doesn't create a result string. In particular the $csv->string(), $csv->status(), $csv-fields()> and $csv->error_input() methods are meaningless after executing this method.

string

 $line = $csv->string();

This object function returns the input to parse() or the resultant CSV string of combine(), whichever was called more recently.

parse

 $status = $csv->parse($line);

This object function decomposes a CSV string into fields, returning success or failure. Failure can result from a lack of argument or the given CSV string is improperly formatted. Upon success, fields() can be called to retrieve the decomposed fields . Upon failure, the value returned by fields() is undefined and error_input() can be called to retrieve the invalid argument.

You may use the types() method for setting column types. See the description below.

getline

 $columns = $csv->getline($io);

This is the counterpart to print, like parse is the counterpart to combine: It reads a row from the IO object $io using $io->getline() and parses this row into an array ref. This array ref is returned by the function or undef for failure.

The $csv->string(), $csv->fields() and $csv->status() methods are meaningless, again.

types

 $csv->types(\@tref);

This method is used to force that columns are of a given type. For example, if you have an integer column, two double columns and a string column, then you might do a

 $csv->types([Text::CSV_XS::IV(),
              Text::CSV_XS::NV(),
              Text::CSV_XS::NV(),
              Text::CSV_XS::PV()]);

Column types are used only for decoding columns, in other words by the parse() and getline() methods.

You can unset column types by doing a

 $csv->types(undef);

or fetch the current type settings with

 $types = $csv->types();

fields

 @columns = $csv->fields();

This object function returns the input to combine() or the resultant decomposed fields of parse(), whichever was called more recently.

status

 $status = $csv->status();

This object function returns success (or failure) of combine() or parse(), whichever was called more recently.

error_input

 $bad_argument = $csv->error_input();

This object function returns the erroneous argument (if it exists) of combine() or parse(), whichever was called more recently.

EXAMPLE

  require Text::CSV_XS;

  my $csv = Text::CSV_XS->new;

  my $column = '';
  my $sample_input_string = '"I said, ""Hi!""",Yes,"",2.34,,"1.09"';
  if ($csv->parse($sample_input_string)) {
    my @field = $csv->fields;
    my $count = 0;
    for $column (@field) {
      print ++$count, " => ", $column, "\n";
    }
    print "\n";
  } else {
    my $err = $csv->error_input;
    print "parse() failed on argument: ", $err, "\n";
  }

  my @sample_input_fields = ('You said, "Hello!"',
                             5.67,
                             'Surely',
                             '',
                             '3.14159');
  if ($csv->combine(@sample_input_fields)) {
    my $string = $csv->string;
    print $string, "\n";
  } else {
    my $err = $csv->error_input;
    print "combine() failed on argument: ", $err, "\n";
  }

CAVEATS

This module is based upon a working definition of CSV format which may not be the most general.

1. Allowable characters within a CSV field include 0x09 (tab) and the inclusive range of 0x20 (space) through 0x7E (tilde). In binary mode all characters are accepted, at least in quoted fields:

2. A field within CSV may be surrounded by double-quotes. (The quote char)

3. A field within CSV must be surrounded by double-quotes to contain a comma. (The separator char)

4. A field within CSV must be surrounded by double-quotes to contain an embedded double-quote, represented by a pair of consecutive double-quotes. In binary mode you may additionally use the sequence "0 for representation of a NUL byte.

5. A CSV string may be terminated by 0x0A (line feed) or by 0x0D,0x0A (carriage return, line feed).

AUTHOR

Alan Citterman <alan@mfgrtl.com> wrote the original Perl module. Please don't send mail concerning Text::CSV_XS to Alan, as he's not involved in the C part which is now the main part of the module.

Jochen Wiedmann <joe@ispsoft.de> rewrote the encoding and decoding in C by implementing a simple finite-state machine and added the variable quote, escape and separator characters, the binary mode and the print and getline methods.

SEE ALSO

perl(1), IO::File(3), IO::Wrap(3)