In: |
csv.rb
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Parent: | Object |
This module is copyrighted free software by NAKAMURA, Hiroshi. You can redistribute it and/or modify it under the same term as Ruby.
SYNOPSIS
1. reader = CSV.open(filename, 'r') 2. CSV.open(filename, 'r') do |row| ... end 3. writer = CSV.open(filename, 'w') 4. CSV.open(filename, 'w') do |writer| ... end
ARGS
filename: filename to open. mode: 'r' for read (parse) 'w' for write (generate) row: an Array of cells which is a parsed line. writer: Created writer instance. See CSV::Writer#<< and CSV::Writer#add_row to know how to generate CSV string.
RETURNS
reader: Create reader instance. To get parse result, see CSV::Reader#each. writer: Created writer instance. See CSV::Writer#<< and CSV::Writer#add_row to know how to generate CSV string.
DESCRIPTION
Open a CSV formatted file to read or write.
EXAMPLE 1
reader = CSV.open('csvfile.csv', 'r') row1 = reader.shift row2 = reader.shift if row2.empty? p 'row2 not find.' end reader.close
EXAMPLE 2
CSV.open('csvfile.csv', 'r') do |row| p row end
EXAMPLE 3
writer = CSV.open('csvfile.csv', 'w') writer << ['r1c1', 'r1c2'] << ['r2c1', 'r2c2'] << [nil, nil] writer.close
EXAMPLE 4
CSV.open('csvfile.csv', 'w') do |writer| writer << ['r1c1', 'r1c2'] writer << ['r2c1', 'r2c2'] writer << [nil, nil] end
# File csv.rb, line 192 def CSV.open(filename, mode, col_sep = ?,, row_sep = nil, &block) if mode == 'r' or mode == 'rb' open_reader(filename, col_sep, row_sep, &block) elsif mode == 'w' or mode == 'wb' open_writer(filename, col_sep, row_sep, &block) else raise ArgumentError.new("'mode' must be 'r', 'rb', 'w', or 'wb'") end end
# File csv.rb, line 202 def CSV.parse(filename, col_sep = ?,, row_sep = nil, &block) open_reader(filename, col_sep, row_sep, &block) end
# File csv.rb, line 206 def CSV.generate(filename, col_sep = ?,, row_sep = nil, &block) open_writer(filename, col_sep, row_sep, &block) end
SYNOPSIS
cells = CSV.parse_line(src, col_sep = ?,, row_sep = nil)
ARGS
src: a CSV 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
cells: an Array of parsed cells in first line. Each cell is a String.
DESCRIPTION
Parse one line from given string. Bare 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.
# File csv.rb, line 726 def CSV.parse_line(src, col_sep = ?,, row_sep = nil) idx = 0 res_type = :DT_COLSEP cells = Row.new begin while (res_type.equal?(:DT_COLSEP)) cell = Cell.new res_type, idx = parse_body(src, idx, cell, col_sep, row_sep) cells.push(cell.is_null ? nil : cell.data) end rescue IllegalFormatError return Row.new end cells end
SYNOPSIS
str = CSV.generate_line(cells, col_sep = ?,, row_sep = nil)
ARGS
cells: an Array of cell to be converted to CSV string. Each cell must respond to 'to_s'. 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
str: a String of generated CSV string.
DESCRIPTION
Create a line from cells. Each cell is stringified by to_s.
# File csv.rb, line 760 def CSV.generate_line(cells, col_sep = ?,, row_sep = nil) if (cells.size == 0) return '' end res_type = :DT_COLSEP result_str = '' idx = 0 while true cell = if (cells[idx].nil?) Cell.new('', true) else Cell.new(cells[idx].to_s, false) end generate_body(cell, result_str, col_sep, row_sep) idx += 1 if (idx == cells.size) break end generate_separator(:DT_COLSEP, result_str, col_sep, row_sep) end result_str end
SYNOPSIS
parsed_cells, idx = CSV.parse_row(src, idx, out_dev, col_sep = ?,, row_sep = nil)
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 '<<(CSV::Cell)'. 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'.
DESCRIPTION
Parse a line from string. 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
# File csv.rb, line 816 def CSV.parse_row(src, idx, out_dev, col_sep = ?,, row_sep = nil) idx_backup = idx parsed_cells = 0 res_type = :DT_COLSEP begin while (!res_type.equal?(:DT_ROWSEP)) cell = Cell.new res_type, idx = parse_body(src, idx, cell, col_sep, row_sep) if res_type.equal?(:DT_EOS) if idx == idx_backup #((parsed_cells == 0) && (cell.is_null)) 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
SYNOPSIS
parsed_cells = CSV.generate_row(src, cells, out_dev, col_sep = ?,, row_sep = nil)
ARGS
src: an Array of CSV::Cell to be converted to CSV string. Must respond to 'size' and '[](idx)'. src[idx] must return CSV::Cell. 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.
DESCRIPTION
Convert a line from cells data to string. To generate multi-row CSV string, See EXAMPLE below.
EXAMPLE
def d(str) CSV::Cell.new(str, false) end row1 = [d('a'), d('b')] row2 = [d('c'), d('d')] row3 = [d('e'), d('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
# File csv.rb, line 875 def CSV.generate_row(src, cells, out_dev, col_sep = ?,, row_sep = nil) src_size = src.size if (src_size == 0) if cells == 0 generate_separator(:DT_ROWSEP, out_dev, col_sep, row_sep) end return 0 end res_type = :DT_COLSEP parsed_cells = 0 generate_body(src[parsed_cells], out_dev, col_sep, row_sep) parsed_cells += 1 while ((parsed_cells < cells) && (parsed_cells != src_size)) generate_separator(:DT_COLSEP, out_dev, col_sep, row_sep) generate_body(src[parsed_cells], out_dev, col_sep, row_sep) parsed_cells += 1 end if (parsed_cells == cells) generate_separator(:DT_ROWSEP, out_dev, col_sep, row_sep) else generate_separator(:DT_COLSEP, out_dev, col_sep, row_sep) end parsed_cells end