f: First only. That is,replace/find/etc. only the first occurrence of something.
r: The substring to find is a regular expression.标准正则表达式(http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html)
m: Multi-line mode for regular expressions. In multi-line mode the expressions ^ and $ match just after or just before,respectively,a line terminator or the end of the string. By default these expressions only match at the beginning and the end of the entire string. Note that ^ and $ doesn't match the line-break character itself.
s: Enables dot-all mode for regular expressions (same as Perl singe-line mode). In dot-all mode,the expression . matches any character,including a line terminator. By default this expression does not match line terminators.
c: Permits whitespace and comments in regular expressions.在正则表达式中允许空格和注释。
· m: Multi-line mode for regular expressions. In multi-line mode the expressions ^ and $ match just after or just before,a line terminator or the end of the string. By default these expressions only match at the beginning and the end of the entire string.
· s: Enables dotall mode for regular expressions (same as Perl singe-line mode). In dotall mode,宋体; line-height:25.2px"> · c: Permits whitespace and comments in regular expressions.