CSV::Writer 類別
注意:請勿直接使用這個類別。這是內部類別。
屬性
headers[R]
lineno[R]
一個 CSV::Writer
會接收一個輸出,準備標頭、格式和輸出。它允許我們在物件中寫入新列並將其倒回。
公開類別方法
new(output, options) 按一下以切換來源
# File lib/csv/writer.rb, line 16 def initialize(output, options) @output = output @options = options @lineno = 0 @fields_converter = nil prepare if @options[:write_headers] and @headers self << @headers end @fields_converter = @options[:fields_converter] end
公開實例方法
<<(row) 按一下以切換來源
新增一列
# File lib/csv/writer.rb, line 31 def <<(row) case row when Row row = row.fields when Hash row = @headers.collect {|header| row[header]} end @headers ||= row if @use_headers @lineno += 1 if @fields_converter quoted_fields = [false] * row.size row = @fields_converter.convert(row, nil, lineno, quoted_fields) end i = -1 converted_row = row.collect do |field| i += 1 quote(field, i) end line = converted_row.join(@column_separator) + @row_separator if @output_encoding line = line.encode(@output_encoding) end @output << line self end
rewind() 按一下以切換來源
倒回至開頭
# File lib/csv/writer.rb, line 64 def rewind @lineno = 0 @headers = nil if @options[:headers].nil? end
私人實例方法
prepare() 按一下以切換來源
# File lib/csv/writer.rb, line 70 def prepare @encoding = @options[:encoding] prepare_header prepare_format prepare_output end
prepare_force_quotes_fields(force_quotes) 按一下以切換來源
# File lib/csv/writer.rb, line 106 def prepare_force_quotes_fields(force_quotes) @force_quotes_fields = {} force_quotes.each do |name_or_index| case name_or_index when Integer index = name_or_index @force_quotes_fields[index] = true when String, Symbol name = name_or_index.to_s if @headers.nil? message = ":headers is required when you use field name " + "in :force_quotes: " + "#{name_or_index.inspect}: #{force_quotes.inspect}" raise ArgumentError, message end index = @headers.index(name) next if index.nil? @force_quotes_fields[index] = true else message = ":force_quotes element must be " + "field index or field name: " + "#{name_or_index.inspect}: #{force_quotes.inspect}" raise ArgumentError, message end end end
prepare_format() 按一下以切換來源
# File lib/csv/writer.rb, line 133 def prepare_format @column_separator = @options[:column_separator].to_s.encode(@encoding) row_separator = @options[:row_separator] if row_separator == :auto @row_separator = InputRecordSeparator.value.encode(@encoding) else @row_separator = row_separator.to_s.encode(@encoding) end @quote_character = @options[:quote_character] force_quotes = @options[:force_quotes] if force_quotes.is_a?(Array) prepare_force_quotes_fields(force_quotes) @force_quotes = false elsif force_quotes @force_quotes_fields = nil @force_quotes = true else @force_quotes_fields = nil @force_quotes = false end unless @force_quotes @quotable_pattern = Regexp.new("[\r\n".encode(@encoding) + Regexp.escape(@column_separator) + Regexp.escape(@quote_character.encode(@encoding)) + "]".encode(@encoding)) end @quote_empty = @options.fetch(:quote_empty, true) end
prepare_header() 按一下以切換來源
# File lib/csv/writer.rb, line 78 def prepare_header headers = @options[:headers] case headers when Array @headers = headers @use_headers = true when String @headers = CSV.parse_line(headers, col_sep: @options[:column_separator], row_sep: @options[:row_separator], quote_char: @options[:quote_character]) @use_headers = true when true @headers = nil @use_headers = true else @headers = nil @use_headers = false end return unless @headers converter = @options[:header_fields_converter] @headers = converter.convert(@headers, nil, 0, []) @headers.each do |header| header.freeze if header.is_a?(String) end end
prepare_output() 按一下以切換來源
# File lib/csv/writer.rb, line 163 def prepare_output @output_encoding = nil return unless @output.is_a?(StringIO) output_encoding = @output.internal_encoding || @output.external_encoding if @encoding != output_encoding if @options[:force_encoding] @output_encoding = output_encoding else compatible_encoding = Encoding.compatible?(@encoding, output_encoding) if compatible_encoding @output.set_encoding(compatible_encoding) @output.seek(0, IO::SEEK_END) end end end end
quote(field, i) 按一下以切換來源
# File lib/csv/writer.rb, line 190 def quote(field, i) if @force_quotes quote_field(field) elsif @force_quotes_fields and @force_quotes_fields[i] quote_field(field) else if field.nil? # represent +nil+ fields as empty unquoted fields "" else field = String(field) # Stringify fields # represent empty fields as empty quoted fields if (@quote_empty and field.empty?) or (field.valid_encoding? and @quotable_pattern.match?(field)) quote_field(field) else field # unquoted field end end end end
quote_field(field) 按一下以切換來源
# File lib/csv/writer.rb, line 181 def quote_field(field) field = String(field) encoded_quote_character = @quote_character.encode(field.encoding) encoded_quote_character + field.gsub(encoded_quote_character, encoded_quote_character * 2) + encoded_quote_character end