The first time you see the following statement is puzzling
($MCFG [' Lockchinaip ']==1
&& (int) $_session[' Adminuserid ']==0
&& substr_count ($_server[' php_self '), '/manage/') ==0
&& (Preg_match ('/zh-c/i ', substr ($_server[' http_accept_language '], 0, 4)) | | preg_match ('/zh/i ', substr ($_ server[' Http_accept_language '], 0, 4)) 0
)
&& js_location ('/unavailable.php ', ', '. Top ');
The above statement does not have the IF keyword, and the processing mechanism of PHP is: When the previous judge is true, it executes the latter statement.
namely: ($MCFG [' Lockchinaip ']==1
&& (int) $_session[' Adminuserid ']==0
&& substr_count ($_server[' php_self '), '/manage/') ==0
&& (Preg_match ('/zh-c/i ', substr ($_server[' http_accept_language '], 0, 4)) | | preg_match ('/zh/i ', substr ($_ server[' Http_accept_language '], 0, 4)) 0
) is true, go to the "/unavailable.php" page.
PHP: (&&) logic and operator usage instructions