regexp
| Charater | Description | |
|---|---|---|
| [a-z] | any character in a-z | |
| [^a-z] | any character not in a-z | |
| { } | qualifier expression | |
| \ | or | |
| \s | white space character (space, tab, enter) | |
| \S | not white space character | |
| ^ | begin string | |
| $ | end string | |
| . | single character except for \n | |
| * | {0,} | |
| + | {1,} | |
| ? | {0,1} |
More syntax, refer to 参考元字符