上到下用sed。

I'd like to change the following patterns:

我想改变以下的模式:

getFoo_Bar

to:

getFoo_bar

(note the lower b)

(注意下b)

Knowing neither foo nor bar, what is the replacement pattern?

不知道foo和bar，什么是替换模式?

I started writing

我开始写

sed 's/\(get[A-Z][A-Za-z0-9]*_\)\([A-Z]\)/\1

but I'm stuck: I want to write "\2 lower case", how do I do that?

但是我被卡住了:我想写“\2小写”，我该怎么做?

Maybe sed is not adapted?

也许sed不适应?

8 个解决方案

#1

s/\(get[A-Z][A-Za-z0-9]*_\)\([A-Z]\)/\1\L\2/g

Test:

测试:

$ echo 'getFoo_Bar' | sed -e 's/\(get[A-Z][A-Za-z0-9]*_\)\([A-Z]\)/\1\L\2/g'
getFoo_bar

#2

To change getFoo_Bar to getFoo_bar using sed :

使用sed更改getFoo_Bar到getFoo_Bar:

echo "getFoo_Bar" | sed 's/^\(.\{7\}\)\(.\)\(.*\)$/\1\l\2\3/'

The upper and lowercase letters are handled by :

上面和小写字母的处理方式是:

\U Makes all text to the right uppercase.
\U使所有的文本到正确的大写。
\u makes only the first character to the right uppercase.
\u只将第一个字符设置为右大写。
\L Makes all text to the right lowercase.
\L使所有的文本到正确的小写。
\l Makes only the first character to the right lower case. (Note its a lowercase letter L)
\l只将第一个字符用于右小写。(注意它是小写字母L)

The example is just one method for pattern matching, just based on modifying a single chunk of text. Using the example, getFoo_BAr transforms to getFoo_bAr, note the A was not altered.

这个示例只是模式匹配的一种方法，只是基于修改一段文本。使用这个例子，getFoo_BAr转换为getFoo_BAr，注意到A没有被修改。

#3

Somewhat shorter:

有些短:

echo getFoo_Bar | sed 's/_\(.\)/_\L\1/'

#4

Shortest I can come up with:

最短的我能想到:

echo getFoo_Bar | sed 's/_./\L&/'

#5

You can use perl for this one:

你可以用perl来做这个:

perl -pe 's/(get[A-Z][A-Za-z0-9]*)_([A-Z])/\1_\l\2/'

The \l is the trick here.

这里有个小技巧。

sed doesn't do upper/lowercase on matched groups.

sed在匹配组上不做大写/小写。

#6

From the FAQ: How do I convert a string to all lowercase or capital letters?

从常见问题:如何将字符串转换为小写字母或大写字母?

#7

If you want to write everything in lowercase just after underscore, than this would work for you:

如果你想在下划线后用小写字母写所有东西，这对你来说很有用:

echo getFoo_Bar | gawk -F_ '{print tolower($2)}'

#8

-2

echo getFoo_Bar | sed 's/[Bb]/\L&/g'

#1

s/\(get[A-Z][A-Za-z0-9]*_\)\([A-Z]\)/\1\L\2/g