In Files

  • csv.rb

CSV

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.

Public Class Methods

foreach(path, rs = nil, &block) click to toggle source 
 
               # File csv.rb, line 93
def CSV.foreach(path, rs = nil, &block)
  open_reader(path, 'r', ',', rs, &block)
end
generate(path, fs = nil, rs = nil, &block) click to toggle source 
 
               # File csv.rb, line 110
def CSV.generate(path, fs = nil, rs = nil, &block)
  open_writer(path, 'w', fs, rs, &block)
end
generate_line(row, fs = nil, rs = nil) click to toggle source

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

 
               # 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
generate_row(src, cells, out_dev, fs = nil, rs = nil) click to toggle source

Convert a line from cells data to string. Consider using ::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.
 
               # 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(path, mode, fs = nil, rs = nil, &block) click to toggle source

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.
 
               # 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(str_or_readable, fs = nil, rs = nil, &block) click to toggle source

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

 
               # 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_line(src, fs = nil, rs = nil) click to toggle source

Parse a line from given string. Bear in mind it parses ONE LINE. Rest of the string is ignored for example “a,brnc,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 ::parse_row instead of this method.

 
               # 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_row(src, idx, out_dev, fs = nil, rs = nil) click to toggle source

Parse a line from string. Consider using ::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'.
 
               # 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
read(path, length = nil, offset = nil) click to toggle source 
 
               # File csv.rb, line 97
def CSV.read(path, length = nil, offset = nil)
  CSV.parse(IO.read(path, length, offset))
end
readlines(path, rs = nil) click to toggle 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

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