JavaScript Regular expression-boundary character

^: Represents the starting position of the string, which represents the start of a row in a multiline match.

/^\w+/ matches the first word in a string.

$: Represents the end position of the string, which represents the end of a row in a multiline match.

/\w+$/ matches the last word in a string.

/@.+$/ matches a mailbox server.

str = "Great Hope make Great mans";

str = str.replace (/$/, "!"); / Insert the desired character at the end of the string

\b: Represents the boundary of a word (not a character), the position between a word and a space,orthe position between a character (\w) and the beginning or end of a string.

str = "Great Hope make Great mans";

Arr_m = Str.match (/\b\w+\b/g);// Extract all the words in the string

Arr_m = [' great ', ' hope ', ' make ', ' great ', ' man ']

\b: Represents a non-word boundary, contrary to "\b"

JavaScript Regular expression-boundary character