Question

编辑：感谢所有帮助人员！我已经在评论部分找到了答案，但是我不知道如何将评论标记为已回答！谢谢Dainius Preimantas回答了我的问题！

我有一个文本文件，想在文本文件中找到某个字符串，然后返回该字符串所在行的编号？例如：

with open("File.txt", "r+") as f:
    f.find(stringvalue)
    linenumber = #whatever line number value is returned

文本文件（“ File.txt”）：

PasswordBank，jack789

BankEpic，Epic1234

Bank1，Bank123

Master，Master123

Answer 1

尝试这样的事情：

f=open('filename.txt','r')
text=f.read().split('\n')
string_to_find='string'
for line in range(text):
    if string_to_find in text[line]:
        return line

以后，在提出问题时，请参阅我们关于how do i ask a good question?的指南

Answer 2

substring = "42 is the answer"
filename = "file.txt"
with open(filename, "r") as file:
    line = file.readline()
    i = 1
    flag = False
    while line:
        if substring in line: #Or any other string matching condition
            flag = True
        if flag:
            break
        line = file.readline()
        i += 1
    if flag:
        print(i)
    else:
        print("Line not found")

Answer 3

此方法100％我为您尝试过

placeholder = 0

file = open("filename.txt", "r")
all_lines = file.readlines()

while placeholder < len(all_lines):
    each_line = all_lines[placeholder]
    if " yourString " in each_line:
        print("yes in line: " + str(placeholder+1))
        placeholder += 1
    else:
        placeholder += 1

如何在文本文件中找到某个字符串的行号？

3 个答案: