Replace space character with regular expression, php

Question

I am using the function preg_replace('/[^0-9A-F]/', '', $string) to accept only numbers and letters but at the moment is not filtering spaces, how can I include that into my reg expression? thanks

Answer 1

preg_replace('/[^0-9A-F ]/', '', $string)

附带说明，您只允许使用A到F的大写字母。如果要所有字母：

 preg_replace('/[^0-9A-Z ]/i', '', $string)

Answer 2

preg_replace('/[^0-9A-F\x20]/', '', $string)

Answer 3

尝试

preg_replace('/[^0-9A-F]/',( )'', $string)