bash 从文本文件中提取多个字符串
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/48120921/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Grep multiple strings from text file
提问by user3255841
Okay so I have a textfile containing multiple strings, example of this -
好的，所以我有一个包含多个字符串的文本文件，例如 -
Hello123
Halo123
Gracias
Thank you
...
I want grep to use these strings to find lines with matching strings/keywords from other files within a directory
我希望 grep 使用这些字符串从目录中的其他文件中查找具有匹配字符串/关键字的行
example of text files being grepped -
文本文件被 grep 的示例 -
123-example-Halo123
321-example-Gracias-com-no
321-example-match
so in this instance the output should be
所以在这种情况下，输出应该是
123-example-Halo123
321-example-Gracias-com-no
回答by Cyrus
With GNU grep:
使用 GNU grep：
grep -f file1 file2
-f FILE: Obtain patterns from FILE, one per line.
-f FILE: 从 FILE 获取模式，每行一个。
Output:
输出：
123-example-Halo123 321-example-Gracias-com-no
回答by Tom Drake
You should probably look at the manpage for grep to get a better understanding of what options are supported by the grep utility. However, there a number of ways to achieve what you're trying to accomplish. Here's one approach:
您可能应该查看 grep 的联机帮助页，以更好地了解 grep 实用程序支持哪些选项。但是，有多种方法可以实现您的目标。这是一种方法：
grep -e "Hello123" -e "Halo123" -e "Gracias" -e "Thank you" list_of_files_to_search
However, since your search strings are already in a separate file, you would probably want to use this approach:
但是，由于您的搜索字符串已经在一个单独的文件中，您可能希望使用这种方法：
grep -f patternFile list_of_files_to_search
回答by Or B
I can think of two possible solutions for your question:
对于您的问题，我可以想到两种可能的解决方案：
Use multiple regular expressions - a regular expression for each word you want to find, for example:
grep -e Hello123 -e Halo123 file_to_search.txtUse a single regular expression with an "or" operator. Using Perl regular expressions, it will look like the following:
grep -P "Hello123|Halo123" file_to_search.txt
使用多个正则表达式 - 您要查找的每个单词的正则表达式，例如：
grep -e Hello123 -e Halo123 file_to_search.txt使用带有“或”运算符的单个正则表达式。使用 Perl 正则表达式，它将如下所示：
grep -P "Hello123|Halo123" file_to_search.txt
EDIT:As you mentioned in your comment, you want to use a list of words to find from a file and search in a full directory.
编辑：正如您在评论中提到的，您想使用单词列表从文件中查找并在完整目录中搜索。
You can manipulate the words-to-find file to look like -eflags concatenation:
您可以操作 words-to-find 文件，使其看起来像-e标志连接：
cat words_to_find.txt | sed 's/^/-e "/;s/$/"/' | tr '\n' ' '
This will return something like -e "Hello123" -e "Halo123" -e "Gracias" -e" Thank you", which you can then pass to grepusing xargs:
这将返回类似的内容-e "Hello123" -e "Halo123" -e "Gracias" -e" Thank you"，然后您可以将其传递给grepusing xargs：
cat words_to_find.txt | sed 's/^/-e "/;s/$/"/' | tr '\n' ' ' | dir_to_search/*
As you can see, the last command also searches in all of the files in the directory.
如您所见，最后一个命令还搜索目录中的所有文件。
SECOND EDIT: as PesaThe mentioned, the following command would do this in a much more simple and elegant way:
第二次编辑：正如 PesaThe 所提到的，以下命令将以更简单和优雅的方式执行此操作：
grep -f words_to_find.txt dir_to_search/*
grep -f words_to_find.txt dir_to_search/*
