【发布时间】:2014-01-29 15:59:13
【问题描述】:
我正在尝试在 python 中编写一个程序,该程序在 txt 文件中搜索用户指定的单词并将包含该单词的选定行复制到另一个文件中。
用户还可以选择排除任何单词。
(例如,假设用户搜索单词“exception”并希望排除单词“abc”,那么代码只会复制其中包含“exception”的行,而不是“abc”)。
现在所有工作都将在命令提示符下完成。
输入将是:
file.py test.txt(输入文件) test_mod.txt(输出文件) -e abc(排除-e表示的单词)-s exception(搜索-s表示的单词) 现在用户可以选择输入多个排除词和多个搜索词。
我已经使用 argparse 模块完成了程序并且它运行了。 我的问题是当它搜索单词(排除单词和搜索单词)时,它不考虑空格。例如它会在单词“abcexception”中找到单词“exception”。现在有时我需要这个功能,有时我不需要。这是我现在的代码。
import sys
import os
import argparse
import tempfile
import re
def main(): #main method
try:
parser = argparse.ArgumentParser(description='Copies selected lines from files') #Defining the parser
parser.add_argument('input_file') #Adds the command line arguments to be given
parser.add_argument('output_file')
parser.add_argument('-e',action="append")
parser.add_argument('-s',action="append")
args = parser.parse_args() #Parses the Arguments
user_input1 = (args.e) #takes the word which is to be excluded.
user_input2 = (args.s) #takes the word which is to be included.
def include_exclude(input_file, output_file, exclusion_list=[], inclusion_list=[]): #Function which actually does the file writing and also handles exceptions
if input_file == output_file:
sys.exit("ERROR! Two file names cannot be the same.")
else:
try:
found_s = False #These 3 boolean variables will be used later to handle different exceptions.
found_e = False
found_e1 = True
with open(output_file, 'w') as fo: #opens the output file
with open(input_file, 'r') as fi: #opens the input file
for line in fi: #reads all the line in the input file
if user_input2 != None:
inclusion_words_in_line = map(lambda x: x in line, inclusion_list)#Mapping the inclusion and the exclusion list in a new list in the namespace
if user_input1 != None and user_input2 != None: #This list is defined as a single variable as condition operators cannot be applied to lists
exclusion_words_in_line = map(lambda x: x in line, exclusion_list)
if any(inclusion_words_in_line) and not any(exclusion_words_in_line): #Main argument which includes the search word and excludes the exclusion words
fo.write(line) #writes in the output file
found_s = True
elif user_input1 == None and user_input2 != None: #This portion executes if no exclude word is given,only the search word
if any(inclusion_words_in_line):
fo.write(line)
found_e = True
found_s = True
found_e1 = False
if user_input2 == None and user_input1 != None: #No search word entered
print("No search word entered.")
if not found_s and found_e: #If the search word is not found
print("The search word couldn't be found.")
fo.close()
os.remove(output_file)
elif not found_e and not found_s: #If both are not found
print("\nNOTE: \nCopy error.")
fo.close()
os.remove(output_file)
elif not found_e1: #If only the search word is entered
print("\nNOTE: \nThe exclusion word was not entered! \nWriting only the lines containing search words")
except IOError:
print("IO error or wrong file name.")
fo.close()
os.remove(output_file)
if user_input1 != user_input2 : #this part prevents the output file creation if someone inputs 2 same words creating an anomaly.
include_exclude(args.input_file, args.output_file, user_input1, user_input2);
if user_input1 == user_input2 : #This part prevents the program from running further if both of the words are same
sys.exit('\nERROR!!\nThe word to be excluded and the word to be included cannot be the same.')
except SystemExit as e: #Exception handles sys.exit()
sys.exit(e)
if __name__ == '__main__':
main()
我怎样才能在这个程序中包含另外两个参数,比如:-ew 和 -sw 只搜索整个单词以及 -e 和 -s 搜索单词,即使没有任何空格?所以总共会有4个参数。(-e,-s,-ew,-sw)
【问题讨论】:
标签: python file exception exception-handling argparse