Python学校/学习

Question

我想知道在学习方面寻求帮助是不是可以…但现在它开始了。

在一个课程中，我试着轻松地做了一件我在C#中做过的事情。其思想是将虚构的销售数据放入object数组，进行排序，驱动到bin文件、json文件、xml文件中，从数据中生成10×1000批次的随机订单in，再对这些数据进行二进制搜索，将对象搜索并保存到excel文件中，最后得到一个bin文件、一个json文件、一个xml文件和10个各1000个订单行的excel文件。

这在过程化的方式中是相当容易的，但是当尝试多处理时，它变得非常奇怪。首先，它从上到下一直到行：if __name__ == '__main__'，之后它似乎多次开始执行所有相同的方法……

以下是我的主要内容：

import multiprocessing
import CsvReader
import DataContainer
import FileWriter
from datetime import datetime
import ExcelHandler

processes = []
container = DataContainer.DataContainer() #csv_reader.readFile())
csv_reader = CsvReader.CsvReader(r'C:\Users\jansse\Desktop\opiskelut\Python\finalCapstoneProj\100000 Sales Records.csv', container)
print(f'objects inside from the csv file: {datetime.now().time()}')
print(f"lines: {csv_reader.readFile()}")
print(f'begin sorting: {datetime.now().time()}')
container.sort_container()
print(f'sort done, multiprocessingStart {datetime.now().time()}')
fWriter = FileWriter.FileWriter(container)
p1 = multiprocessing.Process(target=fWriter.write_to_binary)
processes.append(p1)
p2 = multiprocessing.Process(target=fWriter.write_to_json)
processes.append(p2)
p3 = multiprocessing.Process(target=fWriter.generate_XmlFile)
processes.append(p3)
xlHandler = ExcelHandler.ExcelHandler(container)
p4 = multiprocessing.Process(target=xlHandler.rollExcels)
processes.append(p4)


if __name__ == '__main__':

   for p in processes:
       p.start()

   for p in processes:
       p.join()

下面是一个方法的示例：

    def write_to_json(self):
        import json
        print(f'json writing start {datetime.now().time()}')

        try:
            jsonData = ''
            with open('objects.json', 'w') as outputfileJson:
                dEncoder = DataModel.DataEncoder
                json.dump(self.container.returnContainer(), outputfileJson ,cls=dEncoder)
        except Exception as e:
            print(f'Something happened: {e.__class__}, {e.args[0]}')
        finally:
            return (f'json writing completed {datetime.now().time()}')

输出结果如下所示。为什么它看起来像是回到了准备数据的方法(比如排序)，为什么它不等待json-write完成，尽管我在声明之后加入了进程？我的调试打印：

objects inside from the csv file: 06:27:33.139741
lines: 100001
begin sorting: 06:27:34.733476
sort done, multiprocessingStart 06:27:34.893071
objects inside from the csv file: 06:27:35.511050
lines: 100001
begin sorting: 06:27:37.111736
sort done, multiprocessingStart 06:27:37.283164
binarywriting start 06:27:38.886788
objects inside from the csv file: 06:27:39.482656
lines: 100001
begin sorting: 06:27:41.124737
sort done, multiprocessingStart 06:27:41.267926
json writing start 06:27:42.855922
objects inside from the csv file: 06:27:43.400854
lines: 100001
begin sorting: 06:27:44.938005
sort done, multiprocessingStart 06:27:45.097263
xml writing start 06:27:46.922682
objects inside from the csv file: 06:27:47.495836
lines: 100001
begin sorting: 06:27:49.225932
sort done, multiprocessingStart 06:27:49.397371
Excel writing start 06:27:51.089208
excelfile generating:0
excelfile generating:1
excelfile generating:2
excelfile generating:3
excelfile generating:4
excelfile generating:5
excelfile generating:6
excelfile generating:7
excelfile generating:8
excelfile generating:9
Excel writing completed 06:27:56.816604
xml writing completed 06:28:27.855510

Answer 1

PYPL:这很有帮助！谢谢:)

import multiprocessing
import DataContainer
import FileWriter
from datetime import datetime
import ExcelHandler
import CreateContainer

if __name__ == '__main__':

    creator = CreateContainer.CreateContainer()
    container = creator.createContainer()

    processes = []
    print(f'multiprocessingStart {datetime.now().time()}')
    fWriter = FileWriter.FileWriter(container)
    p1 = multiprocessing.Process(target=fWriter.write_to_binary)
    processes.append(p1)
    p2 = multiprocessing.Process(target=fWriter.write_to_json)
    processes.append(p2)
    p3 = multiprocessing.Process(target=fWriter.generate_XmlFile)
    processes.append(p3)
    xlHandler = ExcelHandler.ExcelHandler(container)
    p4 = multiprocessing.Process(target=xlHandler.rollExcels)
    processes.append(p4)

    for p in processes:
        p.start()

    for p in processes:
        p.join()

现在打印如下所示：

objects inside from the csv file: 06:05:59.502160
lines: 100001
begin sorting: 06:06:01.256706
containerReady 06:06:01.415215
multiprocessingStart 06:06:01.428252
binarywriting start 06:06:03.183367
json writing start 06:06:04.988768
xml writing start 06:06:06.725813
Excel writing start 06:06:08.561955
excelfile generating:0
excelfile generating:1
excelfile generating:2
excelfile generating:3
excelfile generating:4
excelfile generating:5
excelfile generating:6
excelfile generating:7
excelfile generating:8
excelfile generating:9
Excel writing completed 06:06:15.105672
xml writing completed 06:06:49.466709
json writing completed 06:08:15.298768

...and我没有看到从write_ to _json-method中打印的原因是因为我从那里返回了变量，却忘了把它改成print-method。