Regex to select last line in a multi-line string

问题

I have an ANT script which will have a property whose value could be one or more lines e.g. property

prop1=
A_12.1_REL_B121000_10_18_2011.1700
A_12.1_REL_B121001_10_25_2011.6059
A_12.1_REL_B121001_10_25_2011.2201
A_12.1_REL_B121001_10_25_2011.2014

Please see that all these lines end with a CRLF and end of file is also another CRLF. Now what I need to do is just select the last line using a regex. The number of lines could be less or more e.g

prop1=
    A_12.1_REL_B121000_10_18_2011.1700  

In the second case I need to select this single line . I have searched older posts, but could not find anything specific. Any pointers ?

回答1:

If you are using ant-contrib :

    <loadfile srcFile="input.prop" property="test"/>

    <propertyregex property="result"
                   input="${test}"
                   regexp="(.*$)"
                   select="\1"
    />

    <echo message="Result is : ${result}"/>

This will always print the last line of your input properties file :

[echo] Result is : A_12.1_REL_B121001_10_25_2011.2014

回答2:

This should do it...

/^.*\z/m

See it in action.

(assume the m is multi-line mode.)

来源：https://stackoverflow.com/questions/8178864/regex-to-select-last-line-in-a-multi-line-string