# G.8 Containsregexp The `<containsregexp>` tag selects the files whose contents contain a match to the regular expression specified by the expression attribute. ``` <fileset dir="${src}" includes="*.txt"> <containsregexp expression="[4-6]\.[0-9]"/> </fileset> ``` Table G.8:聽 Attributes for the `<containsregexp>` selector NameDescriptionDefaultRequired`expression`Specifies the regular expression that must match true in every file.n/aYes`casesensitive`Perform a case sensitive match.`true`No`multiline`Perform a multi line match.`false`No