使用Linux终端在.txt中找到animal-060，animal-061，animal-062…，animal-069

Question

I want to find the string animal-0** in a .txt document using the linux terminal. ** are the numbers from 60 to 69. I guess I have to use grep and regex with the command: grep -E 'animal-0[60-69]' animallist.txt

Would this be the correct command, or would it also find ima6 for example, because ima60 is part of the numbers and letters in the ''. Sorry for grammar mistakes, English is not my native language.

Answer 1

You're pretty close! Remember that a regex character classes (sets or ranges between square brackets) look for a range of characters and will match just once unless you specify otherwise with * or + etc. In your example, [60-69] is the same as [690-6] which will match any single 6 , 9 , or charater in the range 0-6 . To find the numbers between 60 and 69, we must look at the numbers as a string.

Take this as an example: Instead of "60" to "69", let's assume we are looking for "Za" to "Zj". In this case we would use the pattern Z[aj] .

Using the above example on your problem, we can take "6" instead of "Z" and replace "aj" with "0-9", giving us the pattern:

animal-06[0-9]

As a complete command, this would be:

grep -E 'animal-06[0-9]' animallist.txt

Answer 2

是的，如果您将使用grep -E 'animal-06[0-9]' animallist.txt ，它将起作用

Answer 3

grep -E 'animal-06[0-9]' animallist.txt 

And no, it wouldn't find ima60. Your [60-69] won't do what you think, either. Find a good resource that teaches RegEx.