Form feed (\u000C)
\
Backslash itself (\u005C)
\'
Single quote (\u0027)
\"
Double quote (\u0022)
\ddd
An octal char, with each d being an octal digit ( 07 )
\uxxxx
A Unicode char, with each x being a hex digit ( 09 , af, AF)
Table 4. Regular Expression Special Characters
Construct
Matches
CHARACTERS
x
The character x
\
backslash
\0n
character with octal value 0n
\0nn
character with octal value 0nn
\0nnn
character with octal value 0nnn (nnn 377)
\xhh