Python 3在文本文件中每行搜索關鍵字不止一次

Question

使用一個簡單的腳本來搜索某個文件中的關鍵字。一旦找到關鍵字，就會計算它使用的次數，然後將每次找到關鍵字的行號記錄到列表中。然後打印出它被發現的次數和行數。 該程序計算關鍵字罰款，但它被發現一次後，它會進入下一行。它不會計算多個關鍵字。我知道它是這樣做的，因爲if語句：if keyword in line: Number_Of_Key_Words = Number_Of_Key_Words + 1 found_at.append(num) continue

如何獲得它以說明每行文件可能存在多個關鍵字？

全碼：

def search(): 
Number_Of_Key_Words = 0 
found_at = []; 
keyword = input("Enter a key word to search for: ") 
with open("WordList.txt") as file: 
    for num, line in enumerate(file, 1): 
     if keyword in line: 
      Number_Of_Key_Words = Number_Of_Key_Words + 1 
      found_at.append(num) 
      continue 
    print(Number_Of_Key_Words) 
    print("Found on lines: ", found_at) 
search() 

例 單詞列表

字逐字

搜索 「字」 輸出：1
上系中發現[1]

想要： 輸出：3
找到線路[1]

Answer 1

一種方法是使用re模塊findall，它會查找字符串中的所有匹配項。

像這樣的東西（我也提出了一些修改）：

import re 

keyword = input("...") 
found_at = [] 
counter = 0 # Number_Of_Key_Words is not a good python name 
# file is a PY2 built in, so I use 'f' instead 
# also you should be explicit for the open mode, 'r' == read mode 
with open("...", "r") as f: 
    for num, line in enumerate(f, 1): 
     # re.findall() will return a list of all keyword occurrence 
     # len() will then measure the occurrence effectively 
     count = len(re.findall(keyword, line)) 
     if count > 0: # ie. keyword in line at least once 
      found_at.append(num) 
      counter += count 

    print(found_at) 
    print(counter) 

希望這有助於。

Answer 2

備選地，可以使用 「str.count（關鍵字，開始，結束）」

樣品數據 「wordtext.txt」：

red, blue, red, green. 
blue, yellow, white. 
green, orange. 
red, blue, green, red, black, yellow, red. 

輸出：

>>> with open ('wordtext.txt') as f: 
    for i, line in enumerate (f): 
     found = line.count ('red') 
     if found: 
      print ('Line: %d Red: %d' % (i, found)) 


Line: 0 Red: 2 
Line: 3 Red: 3 
>>>