如何从 python 模块运行具有无限循环的多个 .py 文件？

Question

我有两个文件。我们称它为 file_X.py 和 file_Y.py。两者都有从 COM 端口连续读取数据的无限循环。我有一个 tkinter 模块，它有两个按钮来启动 file_X 和 file_Y。因此，如果我单击按钮 A，我希望 file_X 运行，而按钮 B 将启动 file_Y。如何并行运行这些文件并让它们在各自的命令提示符终端中显示数据？

我尝试使用 runpy 和 os.system。 os.system 会给我一个错误，即使这两个文件的模块都可以自己正常工作。另一方面，runpy 不允许我在第一个模块运行时单击另一个按钮。

Tkinter 模块：

import tkinter as tk
import time

import runpy

root = tk.Tk()
root. title("App")
root.geometry('700x500')

v = tk.IntVar()
v.set(-1)

button_labels = [
    (" Device 1 "),
    (" Device 2 ")]

def ShowChoice():
    choice = v.get() + 1
    if(choice == 1):
        runpy.run_module('file_X', run_name='__main__')

    elif(choice == 2):
        runpy.run_module('file_Y', run_name='__main__')

tk.Label(root, 
         text="""Choose the device you want to launch:""",
         font = 'Arial 20 bold',
         justify = tk.LEFT,
         height = 6,
         padx = 20).pack()

for val, button_label in enumerate(button_labels):
    tk.Radiobutton(root,
                   text = button_label,
                   font = 'Times 12 bold',
                   indicatoron = 0,
                   bg = 'cornflower blue',
                   width = 40,
                   padx = 20,
                   pady = 5,
                   variable=v,
                   command=ShowChoice,
                   value=val).pack(anchor=tk.S)

root.mainloop()

file_X 和 file_Y 的代码几乎相同，但连接到不同的 COM 端口并具有不同的字符串修改。

import serial
import time
import csv

try:
ser = serial.Serial("COM4",
                     baudrate=2400,
                     bytesize=serial.EIGHTBITS,
                     parity =serial.PARITY_ODD)

except:
        print("Device not detected")   

def Reader():
    global ser
    try:                    
        data = ser.readline().decode('utf-8')
        data = str(data).replace("\r\n","")
        data = data.replace("\x000","")
        return data
    except:
        return "Data Unavailable"

def Start():
    date_now = time.strftime('%d.%m.%y')
    time_now = time.strftime('%H.%M.%S')
    file_name = date_now + '__' + time_now + '.csv'

    with open(file_name, 'w+') as f:
        csv_file = csv.writer(f)
        csv_file.writerow(['DATE','TIME','VALUE'])  

        while True:
            date_now = time.strftime('%d/%m/%y')
            time_now = time.strftime('%H:%M:%S')
            data = Reader()
            csv_file.writerow([date_now, time_now, data])
            print([date_now, time_now, data])

if __name__ =='__main__':

    Start()

Answer 1

您可以使用线程、多处理或子进程模块。

这是一个演示线程模块的快速示例。

import threading, time

def Start(name=''):
    cnt=0
    while(cnt<10):
        cnt+=1
        print "This is thread %s" % name
        time.sleep(1)

thread1 = threading.Thread(target=Start, name='Thread-1', args=('Serial1',))

thread2 = threading.Thread(target=Start, name='Thread-2', args=('Serial2',))

thread2.start()
thread1.start()


while (thread1.isAlive() and thread2.isAlive()):
    time.sleep(2)
    print "Running Threads : %s" % [thread.name for thread in threading.enumerate()]


print "done"

按照建议，您可以导入 file_X 和 file_Y 并使用 Start() 函数作为每个线程的 run() 方法调用的目标（可调用对象）为每个线程创建一个线程。

import file_X, file_Y

thread1 = threading.Thread(target=file_X.Start, name='COM1') 
thread2 = threading.Thread(target=file_Y.Start, name='COM2')
thread1.start()
thread2.start()

多处理模块类似于线程。

使用 subprocess 模块交替运行 file_X 和 file_Y 作为子进程。

新的

import threading
import time
import serial
import sys, os.path
import csv


def OpenSerialPort(port=""):
    print ("Open port %s" % port)

    serPort = None

    try:
        serPort = serial.Serial(port,
                    baudrate=2400,
                    bytesize=serial.EIGHTBITS,
                    parity =serial.PARITY_ODD)

    except serial.SerialException as msg:
        print( "Error opening serial port %s" % msg)

    except:
        exctype, errorMsg = sys.exc_info()[:2]
        print ("%s  %s" % (errorMsg, exctype))

    return serPort


def Reader(file_name, serialPort, stopped):
    print ("Start reading serial port %s." % serialPort.name)

    serialPort.timeout = 1.0
    while not stopped.is_set(): 
        serData = ''       
        try:                    
            #print "Reading port..."
            serData = serialPort.readline()

        except:
            exctype, errorMsg = sys.exc_info()[:2]
            print ("Error reading port - %s" % errorMsg)
            stopped.set()
            break

        if len(serData) > 0:
            serData = serData.decode('utf-8')
            serData = str(serData).replace("\r\n","")
            serData = serData.replace("\x000","")
            Log_Data(file_name, serData)
        #else:
        #    print("Reader() no Data")

    serialPort.close()
    print ("Reader finished. Closed %s" % serialPort.name)

def Init_Log(portName=''):
    #Create log file
    portName = os.path.basename(portName)
    file_name = time.strftime('%d.%m.%y__%H.%M.%S') + "__%s.csv" % portName
    with open(file_name, 'w') as f:
        csv_file = csv.writer(f)
        csv_file.writerow(['DATE','TIME','VALUE'])

    return file_name    

def Log_Data(file_name='', dataString=''):

    date_now = time.strftime('%d/%m/%y')
    time_now = time.strftime('%H:%M:%S')

    with open(file_name, 'a') as f:
        csv_file = csv.writer(f)
        csv_file.writerow([date_now, time_now, dataString])
        print([date_now, time_now, dataString])



if __name__ == "__main__":

    stopped = threading.Event() # Create stopped event to notify all threads when it is time to stop.

    #Open COM3 ports
    portName = 'COM3'
    serialPort_1 = OpenSerialPort(portName)
    if serialPort_1 == None: 
        sys.exit(1)
    file_name_1 = Init_Log(portName) #Create log file

    p1 = threading.Thread(target=Reader, args=(file_name_1, serialPort_1, stopped,))


    #Open COM4 ports
    portName = 'COM4'
    serialPort_2 = OpenSerialPort(portName)
    if serialPort_2 == None: 
        sys.exit(1)
    #Create log file
    file_name_2 = Init_Log(portName)
    p2 = threading.Thread(target=Reader, args=(file_name_2, serialPort_2, stopped,))


    #Start port reader threads
    p1.start()
    p2.start()

    #This is just a test loop that does nothing for awhile.
    loopcnt = 20
    while (loopcnt > 0) and (not stopped.is_set()):
        loopcnt -= 1
        print ("main() %d" % loopcnt)

        try:
            time.sleep(1)

        except KeyboardInterrupt: #Capture Ctrl-C
            print ("Captured Ctrl-C")
            loopcnt=0
            stopped.set()

    stopped.set()
    print ("Stopped")
    p1.join()
    p2.join()

    serialPort_1.close()
    serialPort_2.close()
    print ("Done")