用法：
pretty.pretty_file(文件名, ***options*)
读取 CSV 文件并将数据以表格的形式直观地打印到新文件中。 文件名，是给定的 CSV 文件。可选的 ***options* 关键字参数是 Python 的标准库 csv 模块 Dialects and Formatting Parameters 和以下列表的并集：
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new_delimiter：新的列分隔符（默认“|”）
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border：如果要打印表格的边框，则为布尔值（默认 True）
-
border_vertical_left：表格的左边框（默认“|”）
-
border_vertical_right：表格的右边框（默认“|”）
-
border_horizontal：表格的上下边框（默认“-”）
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border_corner_tl：表格的左上角（默认“+”）
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border_corner_tr：表格的右上角（默认“+”）
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border_corner_bl：表格的左下角（默认与border_corner_tl相同）
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border_corner_br：表格的右下角（默认与border_corner_tr相同）
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header：如果第一行是表头，则为布尔值（默认 True）
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border_header_separator：表头与表格的边框（默认同border_horizontal）
-
border_header_left：表头的左边框（默认同border_corner_tl）
-
border_header_right：表头右边框（默认同border_corner_tr）
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new_filename：新文件的文件名（default "new_" + filename）
-
换行：定义表格的行将如何分隔（默认“\n”）
例子：
import pretty_csv
pretty_csv.pretty_file("test.csv", header=False, border=False, delimiter="|")
Python 3：
这是一个 Python 2 实现。对于 Python 3，您必须将出现的 2 行 open(filename, "rb") as input: 更改为 open(filename, "r", newline="") as input:，因为 Python 3 中的 csv.reader 希望文件以文本模式打开。
模块：
import csv
import os
def 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)