Match the regular expression to the tab. t seems to match spaces.

If it is positive, it matches the tab. t seems to match spaces. if it is positive, it matches the tab. if it is not, it also matches spaces. ------ solution ------------------ what is so possible? The analysis is as follows: $ s & nbsp; add a tab with a space and echo & nbsp; the current regular expression matches the tab. \ t may also match spaces.
If the value is positive, it matches the tab. \ t seems to match spaces.

------ Solution --------------------
What is so possible? The analysis is as follows:

$ S = ''; // add a tab with a space
Echo current (unpack ('H * ', $ s); // 2009 20 is the hexadecimal code of the space, and 09 is the hexadecimal code of the Tab key.

Preg_match ("/\ t +/", $ s, $ r );
Echo current (unpack ('H * ', $ r [0]); // get 09

Preg_match ("/+/", $ s, $ r );
Echo current (unpack ('H * ', $ r [0]); // get 20

Preg_match ("/\ s +/", $ s, $ r );
Echo current (unpack ('H * ', $ r [0]); // Get 2009