楔子
我们用 MySQL 客户端查询数据的时候,是以下面这种格式显示的:
内容展示的非常漂亮,而 Python 有一个第三方模块叫 prettytable,专门用来将数据以上面这种格式输出,我们来看一下用法。
添加表头、添加行、添加列
类似于数据库中的表,由表头(或者说字段名),以及每一行的内容组成。
from prettytable import PrettyTable # 传入的 name、age、country 相当于表头 tb = PrettyTable(["name", "age", "country"]) # 调用 add_row 添加行记录 tb.add_row(["Jack Morrison", 49, "America"]) tb.add_row(["Shimada Genji", 35, "Japan"]) tb.add_row(["Shimada Hanzo", 38, "Japan"]) tb.add_row(["Angela Ziegler", 37, "Switzerland"]) print(tb) """ +----------------+-----+-------------+ | name | age | country | +----------------+-----+-------------+ | Jack Morrison | 49 | America | | Shimada Genji | 35 | Japan | | Shimada Hanzo | 38 | Japan | | Angela Ziegler | 37 | Switzerland | +----------------+-----+-------------+ """
如果在编写的过程中,我们需要临时添加一列,prettytable 也是支持的。
from prettytable import PrettyTable tb = PrettyTable(["name", "age", "country"]) tb.add_row(["Jack Morrison", 49, "America"]) tb.add_row(["Shimada Genji", 35, "Japan"]) tb.add_row(["Shimada Hanzo", 38, "Japan"]) tb.add_row(["Angela Ziegler", 37, "Switzerland"]) # 调用 add_column 添加一列 tb.add_column("gender", ["male", "male", "male", "female"]) print(tb) """ +----------------+-----+-------------+--------+ | name | age | country | gender | +----------------+-----+-------------+--------+ | Jack Morrison | 49 | America | male | | Shimada Genji | 35 | Japan | male | | Shimada Hanzo | 38 | Japan | male | | Angela Ziegler | 37 | Switzerland | female | +----------------+-----+-------------+--------+ """
输出内容是不是和 MySQL数据库类似呢。
此外 prettytable 还支持从 csv、数据库、html 等数据源中导入数据,但说实话,从数据源读取数据我们一般使用 pandas,并且还会伴随着数据处理。而使用 prettytable 只是为了让程序中产生的信息,能够以结构化的形式打印,很少会从文件或数据库里面读数据。
输出指定行、指定列
我们也可以输出 table 的指定行、指定列。
from prettytable import PrettyTable tb = PrettyTable(["name", "age", "country", "gender"]) tb.add_row(["Jack Morrison", 49, "America", "male"]) tb.add_row(["Shimada Genji", 35, "Japan", "male"]) tb.add_row(["Shimada Hanzo", 38, "Japan", "male"]) tb.add_row(["Angela Ziegler", 37, "Switzerland", "female"]) # 只输出 name 和 age 两列 # start 和 end 表示开始和结束的行数(从 0 开始) print(tb.get_string(fields=["name", "age"], start=1, end=3)) """ +---------------+-----+ | name | age | +---------------+-----+ | Shimada Genji | 35 | | Shimada Hanzo | 38 | +---------------+-----+ """ # 此外可以用来进行排序 print(tb.get_string(sortby="age", reversesort=True)) """ +----------------+-----+-------------+--------+ | name | age | country | gender | +----------------+-----+-------------+--------+ | Jack Morrison | 49 | America | male | | Shimada Hanzo | 38 | Japan | male | | Angela Ziegler | 37 | Switzerland | female | | Shimada Genji | 35 | Japan | male | +----------------+-----+-------------+--------+ """
设置表格样式
表格也支持几种不同的样式,供我们选择。
from prettytable import * tb = PrettyTable(["name", "age", "country", "gender"]) tb.add_row(["Jack Morrison", 49, "America", "male"]) tb.add_row(["Shimada Genji", 35, "Japan", "male"]) tb.add_row(["Shimada Hanzo", 38, "Japan", "male"]) tb.add_row(["Angela Ziegler", 37, "Switzerland", "female"]) # 样式支持以下几种: # DEFAULT、MSWORD_FRIENDLY、PLAIN_COLUMNS、RANDOM # 之前的样式就是 DEFAULT tb.set_style(MSWORD_FRIENDLY) print(tb) """ | name | age | country | gender | | Jack Morrison | 49 | America | male | | Shimada Genji | 35 | Japan | male | | Shimada Hanzo | 38 | Japan | male | | Angela Ziegler | 37 | Switzerland | female | """ tb.set_style(PLAIN_COLUMNS) print(tb) """ name age country gender Jack Morrison 49 America male Shimada Genji 35 Japan male Shimada Hanzo 38 Japan male Angela Ziegler 37 Switzerland female """ tb.set_style(RANDOM) print(tb) """ ;+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++; . name age country gender . ;+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++; . Jack Morrison 49 America male . . Shimada Genji 35 Japan male . . Shimada Hanzo 38 Japan male . . Angela Ziegler 37 Switzerland female . ;+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++; """
说实话,还是默认的 DEFAULT 样式最好看。
设置对齐方式
from prettytable import * tb = PrettyTable(["name", "age", "country", "gender"]) tb.add_row(["Jack Morrison", 49, "America", "male"]) tb.add_row(["Shimada Genji", 35, "Japan", "male"]) tb.add_row(["Shimada Hanzo", 38, "Japan", "male"]) tb.add_row(["Angela Ziegler", 37, "Switzerland", "female"]) # l 代表左对齐,c 代表居中,r 代表右对齐 # 默认居中 tb.align["name"] = "l" tb.align["age"] = "c" tb.align["country"] = "r" print(tb) """ +----------------+-----+-------------+--------+ | name | age | country | gender | +----------------+-----+-------------+--------+ | Jack Morrison | 49 | America | male | | Shimada Genji | 35 | Japan | male | | Shimada Hanzo | 38 | Japan | male | | Angela Ziegler | 37 | Switzerland | female | +----------------+-----+-------------+--------+ """
设置边框样式
在 PrettyTable 中,边框由三个部分组成:横边框,竖边框,和边框连接符,我们都可以修改。
from prettytable import * tb = PrettyTable(["name", "age", "country", "gender"]) tb.add_row(["Jack Morrison", 49, "America", "male"]) tb.add_row(["Shimada Genji", 35, "Japan", "male"]) tb.add_row(["Shimada Hanzo", 38, "Japan", "male"]) tb.add_row(["Angela Ziegler", 37, "Switzerland", "female"]) # 是否显示边框,默认为True tb.border = True # 横边框 tb.horizontal_char = '^' # 竖边框 tb.vertical_char = '>' # 边框连接符 tb.junction_char='~' print(tb) """ ~^^^^^^^^^^^^^^^^~^^^^^~^^^^^^^^^^^^^~^^^^^^^^~ > name > age > country > gender > ~^^^^^^^^^^^^^^^^~^^^^^~^^^^^^^^^^^^^~^^^^^^^^~ > Jack Morrison > 49 > America > male > > Shimada Genji > 35 > Japan > male > > Shimada Hanzo > 38 > Japan > male > > Angela Ziegler > 37 > Switzerland > female > ~^^^^^^^^^^^^^^^^~^^^^^~^^^^^^^^^^^^^~^^^^^^^^~ """
小结
以上就是 PrettyTable 相关的内容,大部分情况下我们使用默认的样式即可。