Class CSV
In: csv.rb
Parent: Object

This program is copyrighted free software by NAKAMURA, Hiroshi. You can redistribute it and/or modify it under the same terms of Ruby’s license; either the dual license version in 2003, or any later version.

Methods

Classes and Modules

Class CSV::BasicWriter
Class CSV::Cell
Class CSV::IOBuf
Class CSV::IOReader
Class CSV::IllegalFormatError
Class CSV::Reader
Class CSV::Row
Class CSV::StreamBuf
Class CSV::StringReader
Class CSV::Writer

Public Class methods

[Source]

# File csv.rb, line 93
  def CSV.foreach(path, rs = nil, &block)
    open_reader(path, 'r', ',', rs, &block)
  end

[Source]

# File csv.rb, line 110
  def CSV.generate(path, fs = nil, rs = nil, &block)
    open_writer(path, 'w', fs, rs, &block)
  end

Create a line from cells. each cell is stringified by to_s.

[Source]

# File csv.rb, line 160
  def CSV.generate_line(row, fs = nil, rs = nil)
    if row.size == 0
      return ''
    end
    fs ||= ','
    if fs.is_a?(Fixnum)
      fs = fs.chr
    end
    if !rs.nil? and rs.is_a?(Fixnum)
      rs = rs.chr
    end
    res_type = :DT_COLSEP
    result_str = ''
    idx = 0
    while true
      generate_body(row[idx], result_str, fs, rs)
      idx += 1
      if (idx == row.size)
        break
      end
      generate_separator(:DT_COLSEP, result_str, fs, rs)
    end
    result_str
  end

Convert a line from cells data to string. Consider using CSV.generate_line instead. To generate multi-row CSV string, see EXAMPLE below.

EXAMPLE

  row1 = ['a', 'b']
  row2 = ['c', 'd']
  row3 = ['e', 'f']
  src = [row1, row2, row3]
  buf = ''
  src.each do |row|
    parsed_cells = CSV.generate_row(row, 2, buf)
    puts "Created #{ parsed_cells } cells."
  end
  p buf

ARGS

  src: an Array of String to be converted to CSV string.  Must respond to
    'size' and '[](idx)'.  src[idx] must return String.
  cells: num of cells in a line.
  out_dev: buffer for generated CSV string.  Must respond to '<<(string)'.
  col_sep: Column separator.  ?, by default.  If you want to separate
    fields with semicolon, give ?; here.
  row_sep: Row separator.  nil by default.  nil means "\r\n or \n".  If you
    want to separate records with \r, give ?\r here.

RETURNS

  parsed_cells: num of converted cells.

[Source]

# File csv.rb, line 271
  def CSV.generate_row(src, cells, out_dev, fs = nil, rs = nil)
    fs ||= ','
    if fs.is_a?(Fixnum)
      fs = fs.chr
    end
    if !rs.nil? and rs.is_a?(Fixnum)
      rs = rs.chr
    end
    src_size = src.size
    if (src_size == 0)
      if cells == 0
        generate_separator(:DT_ROWSEP, out_dev, fs, rs)
      end
      return 0
    end
    res_type = :DT_COLSEP
    parsed_cells = 0
    generate_body(src[parsed_cells], out_dev, fs, rs)
    parsed_cells += 1
    while ((parsed_cells < cells) and (parsed_cells != src_size))
      generate_separator(:DT_COLSEP, out_dev, fs, rs)
      generate_body(src[parsed_cells], out_dev, fs, rs)
      parsed_cells += 1
    end
    if (parsed_cells == cells)
      generate_separator(:DT_ROWSEP, out_dev, fs, rs)
    else
      generate_separator(:DT_COLSEP, out_dev, fs, rs)
    end
    parsed_cells
  end

Open a CSV formatted file for reading or writing.

For reading.

EXAMPLE 1

  CSV.open('csvfile.csv', 'r') do |row|
    p row
  end

EXAMPLE 2

  reader = CSV.open('csvfile.csv', 'r')
  row1 = reader.shift
  row2 = reader.shift
  if row2.empty?
    p 'row2 not find.'
  end
  reader.close

ARGS

  filename: filename to parse.
  col_sep: Column separator.  ?, by default.  If you want to separate
    fields with semicolon, give ?; here.
  row_sep: Row separator.  nil by default.  nil means "\r\n or \n".  If you
    want to separate records with \r, give ?\r here.

RETURNS

  reader instance.  To get parse result, see CSV::Reader#each.

For writing.

EXAMPLE 1

  CSV.open('csvfile.csv', 'w') do |writer|
    writer << ['r1c1', 'r1c2']
    writer << ['r2c1', 'r2c2']
    writer << [nil, nil]
  end

EXAMPLE 2

  writer = CSV.open('csvfile.csv', 'w')
  writer << ['r1c1', 'r1c2'] << ['r2c1', 'r2c2'] << [nil, nil]
  writer.close

ARGS

  filename: filename to generate.
  col_sep: Column separator.  ?, by default.  If you want to separate
    fields with semicolon, give ?; here.
  row_sep: Row separator.  nil by default.  nil means "\r\n or \n".  If you
    want to separate records with \r, give ?\r here.

RETURNS

  writer instance.  See CSV::Writer#<< and CSV::Writer#add_row to know how
  to generate CSV string.

[Source]

# File csv.rb, line 83
  def CSV.open(path, mode, fs = nil, rs = nil, &block)
    if mode == 'r' or mode == 'rb'
      open_reader(path, mode, fs, rs, &block)
    elsif mode == 'w' or mode == 'wb'
      open_writer(path, mode, fs, rs, &block)
    else
      raise ArgumentError.new("'mode' must be 'r', 'rb', 'w', or 'wb'")
    end
  end

Parse lines from given string or stream. Return rows as an Array of Arrays.

[Source]

# File csv.rb, line 115
  def CSV.parse(str_or_readable, fs = nil, rs = nil, &block)
    if File.exist?(str_or_readable)
      STDERR.puts("CSV.parse(filename) is deprecated." +
        "  Use CSV.open(filename, 'r') instead.")
      return open_reader(str_or_readable, 'r', fs, rs, &block)
    end
    if block
      CSV::Reader.parse(str_or_readable, fs, rs) do |row|
        yield(row)
      end
      nil
    else
      CSV::Reader.create(str_or_readable, fs, rs).collect { |row| row }
    end
  end

Parse a line from given string. Bear in mind it parses ONE LINE. Rest of the string is ignored for example "a,b\r\nc,d" => [‘a’, ‘b’] and the second line ‘c,d’ is ignored.

If you don’t know whether a target string to parse is exactly 1 line or not, use CSV.parse_row instead of this method.

[Source]

# File csv.rb, line 137
  def CSV.parse_line(src, fs = nil, rs = nil)
    fs ||= ','
    if fs.is_a?(Fixnum)
      fs = fs.chr
    end
    if !rs.nil? and rs.is_a?(Fixnum)
      rs = rs.chr
    end
    idx = 0
    res_type = :DT_COLSEP
    row = []
    begin
      while res_type == :DT_COLSEP
        res_type, idx, cell = parse_body(src, idx, fs, rs)
        row << cell
      end
    rescue IllegalFormatError
      return []
    end
    row
  end

Parse a line from string. Consider using CSV.parse_line instead. To parse lines in CSV string, see EXAMPLE below.

EXAMPLE

  src = "a,b\r\nc,d\r\ne,f"
  idx = 0
  begin
    parsed = []
    parsed_cells, idx = CSV.parse_row(src, idx, parsed)
    puts "Parsed #{ parsed_cells } cells."
    p parsed
  end while parsed_cells > 0

ARGS

  src: a CSV data to be parsed.  Must respond '[](idx)'.
    src[](idx) must return a char. (Not a string such as 'a', but 97).
    src[](idx_out_of_bounds) must return nil.  A String satisfies this
    requirement.
  idx: index of parsing location of 'src'.  0 origin.
  out_dev: buffer for parsed cells.  Must respond '<<(aString)'.
  col_sep: Column separator.  ?, by default.  If you want to separate
    fields with semicolon, give ?; here.
  row_sep: Row separator.  nil by default.  nil means "\r\n or \n".  If you
    want to separate records with \r, give ?\r here.

RETURNS

  parsed_cells: num of parsed cells.
  idx: index of next parsing location of 'src'.

[Source]

# File csv.rb, line 214
  def CSV.parse_row(src, idx, out_dev, fs = nil, rs = nil)
    fs ||= ','
    if fs.is_a?(Fixnum)
      fs = fs.chr
    end
    if !rs.nil? and rs.is_a?(Fixnum)
      rs = rs.chr
    end
    idx_backup = idx
    parsed_cells = 0
    res_type = :DT_COLSEP
    begin
      while res_type != :DT_ROWSEP
        res_type, idx, cell = parse_body(src, idx, fs, rs)
        if res_type == :DT_EOS
          if idx == idx_backup #((parsed_cells == 0) and cell.nil?)
            return 0, 0
          end
          res_type = :DT_ROWSEP
        end
        parsed_cells += 1
        out_dev << cell
      end
    rescue IllegalFormatError
      return 0, 0
    end
    return parsed_cells, idx
  end

[Source]

# File csv.rb, line 97
  def CSV.read(path, length = nil, offset = nil)
    CSV.parse(IO.read(path, length, offset))
  end

[Source]

# File csv.rb, line 101
  def CSV.readlines(path, rs = nil)
    reader = open_reader(path, 'r', ',', rs)
    begin
      reader.collect { |row| row }
    ensure
      reader.close
    end
  end

[Validate]