打印包含目标词的文本行

Question

我想在输入所需单词时找到准确的行。例如，如果在一个文本文件中，有 50 行，而 'mirror' 一词位于第 26 行的某处，是否可以打印整行？基本代码写在下面应该可以工作，但没有。

input_text = input("TYPE:")
file = "Library.txt"

with open(file, "r") as txtFile:
    for line in txtFile:
        if input_text in txtFile.read():
            print(line)

        else:
            print("not found!")

Answer 1

尝试 readlines()(or directly file descriptor) in combination with enumerate() 获取该行并将其设置为从 1 开始，这样您就可以获得准确的行而不是手动将其递增 1 (enumerate() starts at 0):

# without readlines()
with open(file, "r") as txtFile:
    for line_num, line in enumerate(txtFile, start=1):
        if input_text in line:
            print(line_num, line)

        else:
            print("not found!")

# with readlines()
with open(file, "r") as txtFile:
    for line_num, line in enumerate(txtFile.readlines(), start=1):
        if input_text in line:
            print(line_num, line)

        else:
            print("not found!")

Answer 2

您需要使用 if input_text in line 而不是 if input_text in txtFile.read()。如果找到该词，您也可以设置一个标志。如果不是，它将打印“未找到”，如下所示：

with open(file, "r") as txtFile:
    found = False

    for line in txtFile:
        if input_text in line:
            print(line)
            found = True
            
    if not found: 
        print("not found!")

Answer 3

input_text = input("TYPE:")
file = "library.txt"

with open(file, "r") as txtFile:
    lines = txtFile.readlines()
    for line in lines:
        if input_text in line:
            print(line)

打印包含目标词的文本行

Printing a text line containing the target word

python

string

txt