Characters Parent topic

Regular Expression
Description
. (dot)
Any character (byte) except newline
x
The character 'x'
\\
The character '\'
\a
The alert (bell) character (ASCII 0x07)
\b
  1. If this meta-symbol is within square brackets [] or by itself, it will be treated as the backspace character (ASCII 0x08). For example, [\b] or \b
  2. If this meta-symbol is at the beginning (or end) of a regular expression, it means any matched string of the regular expression must check whether the left (or right) side of the matched string is a boundary. For example:
    • \bluck > left side must be the boundary
    • luck\b > right side must be the boundary
    • \bluck\b > both sides must be the boundary
  3. If this meta-symbol appears in the middle of a regular expression, it will cause a syntax error.
\f
The form-feed character (ASCII 0x0C)
\n
The newline (line feed) character (ASCII 0x0A)
\r
The carriage-return character (ASCII 0x0D)
\t
The normal (horizontal) tab character (ASCII 0x09)
\v
The vertical tab character (ASCII 0x0B)
\n
The character with octal value 0n (0 <= n <= 7)
\nn
The character with octal value 0nn (0 <= n <= 7)
\mnn
The character with octal value 0mnn (0 <= m <= 3, 0 <= n <= 7)
\xhh
The character with a hexadecimal value 0xhh, for example, \x20 means the space character