用法：
pretty.pretty_file（ filename ， options ）**
读取CSV文件并将数据作为表格直观地打印到新文件中。 filename ，是给定的CSV文件。可选的** options
关键字参数是Python标准库csv模块的方言和格式参数以及以下列表的并集：
- new_delimiter ：新的列分隔符（ 默认为 “ |”）
- border ：如果要打印表格的边框，则为布尔值（ 默认为 True）
- border_vertical_left ：表格的左边框（ 默认为 “ |”）
- border_vertical_right ：表格的右边框（ 默认为 “ |”）
- border_horizontal ：表格的顶部和底部边框（ 默认为 “-”）
- border_corner_tl ：表格的左上角（ 默认为 “ +”）
- border_corner_tr ：表格的右上角（ 默认为 “ +”）
- border_corner_bl ：表格的左下角（ 默认 与 border_corner_tl 相同）
- border_corner_br ：表格的右下角（ 默认 与 border_corner_tr 相同）
- header ：布尔值，如果第一行是表头（ 默认为 True）
- border_header_separator ：标题和表格之间的边界（ 默认 与 border_horizontal 相同）
- border_header_left ：表标题的左边框（ 默认 与 border_corner_tl 相同）
- border_header_right ：表标题的右边框（ 默认 与 border_corner_tr 相同）
- new_filename ：新文件的文件名（ 默认为 “ new_” + filename ）
- newline ：定义如何分隔表的行（ 默认为 “ n”）
例：
import pretty_csvpretty_csv.pretty_file("test.csv", header=False, border=False, delimiter="|")Python 3：
这是一个Python 2实现。对于Python 3，您必须将两次出现的行更改为
open(filename, "rb") asinput:，
open(filename, "r", newline="") as input:因为
csv.reader在Python
3中希望以文本模式打开文件。
模块：
import csvimport osdef pretty_file(filename, **options): """ @summary: Reads a CSV file and prints visually the data as table to a new file. @param filename: is the path to the given CSV file. @param **options: the union of Python's Standard Library csv module Dialects and Formatting Parameters and the following list: @param new_delimiter: the new column separator (default " | ") @param border: boolean value if you want to print the border of the table (default True) @param border_vertical_left: the left border of the table (default "| ") @param border_vertical_right: the right border of the table (default " |") @param border_horizontal: the top and bottom border of the table (default "-") @param border_corner_tl: the top-left corner of the table (default "+ ") @param border_corner_tr: the top-right corner of the table (default " +") @param border_corner_bl: the bottom-left corner of the table (default same as border_corner_tl) @param border_corner_br: the bottom-right corner of the table (default same as border_corner_tr) @param header: boolean value if the first row is a table header (default True) @param border_header_separator: the border between the header and the table (default same as border_horizontal) @param border_header_left: the left border of the table header (default same as border_corner_tl) @param border_header_right: the right border of the table header (default same as border_corner_tr) @param newline: defines how the rows of the table will be separated (default "n") @param new_filename: the new file's filename (*default* "/new_" + filename) """ #function specific options new_delimiter= options.pop("new_delimiter", " | ") border = options.pop("border", True) border_vertical_left = options.pop("border_vertical_left", "| ") border_vertical_right = options.pop("border_vertical_right", " |") border_horizontal = options.pop("border_horizontal", "-") border_corner_tl = options.pop("border_corner_tl", "+ ") border_corner_tr = options.pop("border_corner_tr", " +") border_corner_bl = options.pop("border_corner_bl", border_corner_tl) border_corner_br = options.pop("border_corner_br", border_corner_tr) header = options.pop("header", True) border_header_separator = options.pop("border_header_separator", border_horizontal) border_header_left = options.pop("border_header_left", border_corner_tl) border_header_right = options.pop("border_header_right", border_corner_tr) newline = options.pop("newline", "n") file_path = filename.split(os.sep) old_filename = file_path[-1] new_filename = options.pop("new_filename", "new_" + old_filename) column_max_width = {} #key:column number, the max width of each column num_rows = 0 #the number of rows with open(filename, "rb") as input: #parse the file and determine the width of each column reader=csv.reader(input, **options) for row in reader: num_rows += 1 for col_number, column in enumerate(row): width = len(column) try: if width > column_max_width[col_number]: column_max_width[col_number] = width except KeyError: column_max_width[col_number] = width max_columns = max(column_max_width.keys()) + 1 #the max number of columns (having rows with different number of columns is no problem) if max_columns > 1: total_length = sum(column_max_width.values()) + len(new_delimiter) * (max_columns - 1) left = border_vertical_left if border is True else "" right = border_vertical_right if border is True else "" left_header = border_header_left if border is True else "" right_header = border_header_right if border is True else "" with open(filename, "rb") as input: reader=csv.reader(input, **options) with open(new_filename, "w") as output: for row_number, row in enumerate(reader): max_index = len(row) - 1 for index in range(max_columns): if index > max_index: row.append(' ' * column_max_width[index]) #append empty columns else: diff = column_max_width[index] - len(row[index]) row[index] = row[index] + ' ' * diff #append spaces to fit the max width if row_number==0 and border is True: #draw top border output.write(border_corner_tl + border_horizontal * total_length + border_corner_tr + newline) output.write(left + new_delimiter.join(row) + right + newline) #print the new row if row_number==0 and header is True: #draw header's separator output.write(left_header + border_header_separator * total_length + right_header + newline) if row_number==num_rows-1 and border is True: #draw bottom border output.write(border_corner_bl + border_horizontal * total_length + border_corner_br)
