To match any space character using regular expressions, you can simply use the pattern \s. This pattern matches any whitespace character, including spaces, tabs, and newline characters. If you specifically want to match only space characters (and not tabs or newlines), you can simply use a literal space character. Here's how you can do it:

To match any whitespace character (including spaces, tabs, and newlines):

\s

To match only space characters:

\ 

(Note: There's a space character after the backslash)