使用正則運算式條件迭代.txt檔案

程式作業流程：

1. 打開“asigra_backup.txt”檔案并讀取每一行
2. 搜索確切的字串：“錯誤：” {任何值，范圍為 1 - 100}。例如“錯誤：12”
3. 找到匹配項后，以 write&append 模式打開一個單獨的 .txt 檔案
4. 寫下找到的匹配項。示例：“錯誤：4”
5. 除了上述寫入之外，在步驟 3 中找到的匹配項下方附加接下來的 4 行；因為那是額外的日志資訊我做了什么：
6. 在 regex101.com 上測驗了一個與我的示例資料匹配的正則運算式
7. 使用串列理解在我的測驗檔案中查找所有匹配項我需要幫助的地方（請）：
8. 弄清楚如何在找到的每個匹配字串下方附加 4 行日志資訊

當前代碼：

result = [line.split("\n")[0] for line in open('asigra_backup.txt') if re.match('^Errors:\s([1-9]|[1-9][0-9]|100)',line)]

print(result)

當前輸出：

['Errors: 1', 'Errors: 128']

期望的輸出：

Errors: 1
Pasta
Fish 
Dog
Doctonr
Errors: 128
Lemon
Seasoned
Rhinon
Goat

示例 .TXT 檔案

Errors: 1
Pasta
Fish 
Dog
Doctonr
Errors: 128
Lemon
Seasoned
Rhinon
Goat
Errors: 0 
Rhinon
Cat 
Dog
Fish 

uj5u.com熱心網友回復：

使用更好的正則運算式re.findall可以使它更容易。在以下正則運算式Errors: 中，檢測到所有和以下 4 行。

import re
regex_matches = re.findall('(?:[\r\n] |^)((Errors:\s*([1-9][0-9]?|100))(?:[\r\n\s\t] .*){4})', open('asigra_backup.txt', 'r').read())
open('separate.txt', 'a').write('\n'   '\n'.join([i[0] for i in regex_matches]))

要訪問錯誤編號或錯誤行，可以使用以下行：

error_rows = [i[1] for i in regex_matches]
error_numbers = [i[2] for i in regex_matches]
print(error_rows)
print(error_numbers)

uj5u.com熱心網友回復：

我寫了一個代碼，它按要求列印輸出。Errors: 1將行添加為最后一行時，該代碼將起作用。查看我決議的文本：

data_to_parse = """
Errors: 56
Pasta
Fish 
Dog
Doctonr
Errors: 0
Lemon
Seasoned
Rhinon
Goat
Errors: 45
Rhinon
Cat 
Dog
Fish
Errors: 34
Rhinon
Cat 
Dog
Fish1
Errors: 1
"""

請參閱不使用正則運算式即可提供所需輸出的代碼。索引已用于獲取所需的資料。

lines = data_to_parse.splitlines()

errors_indices = []

i = 0
k = 0

for line in lines: # where Errors: are located are found in saved in list errors_indices. 
    if 'Errors:' in line:
        errors_indices.append(i)
    i = i 1

#counter = False

while k < len(errors_indices):
    counter = False # It is needed to find the indices when Errors: 0 is hit. 
    for j in range(errors_indices[k-1], errors_indices[k]):
        if 'Errors:' in lines[j]:
            lines2 = lines[j].split(':')
            lines2_val = lines2[1].strip()
            if int(lines2_val) != 0:
                print(lines[j])
            if int(lines2_val) == 0:
                counter = True
            
        elif 'Errors:' not in lines[j] and counter == False:
            print(lines[j])
    k=k 1

我已經嘗試了幾次以查看代碼是否正常作業。看起來它正確地給出了請求的輸出。查看代碼運行時的輸出：

uj5u.com熱心網友回復：

對于那些想要進一步澄清的人，因為它可能會幫助下一個人，這是我的最終解決方案：

def errors_to_file(self):
    """
    Opens file containing Asigra backup logs, "asigra_backup.txt",  and returns a list of all errors within the log.
    Uses a regular expression match conditional on each line within the asigra backup log file. Error number range is 1 - 100.
    Formats errors log by appending a space every 10th element in the errors log list.txt
    Writes formatted error log to a file in current directory: "asigra_errors.txt"
    """

    # "asigra_backup.txt" contains log information from the performed backup. 
    with open('asigra_backup.txt', "r") as f:


        lines0 = [line.rstrip() for line in f]  

        # empty list that is appended with errors found in the log
        lines = []

        for i, line in enumerate(lines0):


            if re.match('^Errors:\s([1-9]|[1-9][0-9]|100)',line):  
                lines.extend(lines0[i:i 9]) 
              

    
    if len(lines) == 0: 
        print("No errors found")
        print("Gracefully exiting")
        sys.exit(1)

    k = ''
    N = 9

    formatted_errors = list(chain(*[lines[i : i N]   [k] 
                if len(lines[i : i N]) == N 
                else lines[i : i N] 
                for i in range(0, len(lines), N)]))


    with open("asigra_errors.txt", "w") as e:

        for i, line in enumerate(formatted_errors): 
            e.write(f"{line}\n")   

非常感謝那些回答我問題的人。

標籤：Python 正则表达式 循环 条件语句 匹配

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