Several supplementary functions about session (1)_PHP tutorial

Under PHP, there is a lot of discussion about session. In fact, there are several functions in PHP4 that we usually don't notice.
Let me introduce them to you below.
The session_set_save_handler() is really a good thing.
//**********************
session_unset (PHP4 $#@62;= 4.0b4)
void session_unset(void);
This function can set all registered session variables to empty. Note that it is not unregister, nor is it the same as destroy.
The following example provides a good explanation of this function.
$#@60;?php
session_register("a","b","c"); //auto-session-start
$a=1;
$b=2 ;
$c=3;
session_unregister("a"); //unregistrered $a
echo "A: $a - reg:".session_is_registered("a")."
" ; // but the global $a remains
session_unset(); // unsets $b und $c
echo "B:$b - reg:".session_is_registered("b")."
" ; // the registration remains !
echo "C:$c - reg:".session_is_registered("c")."
";
echo session_encode();
?$#@62 ;
Output:
A: 1 - reg:
B: - reg:1
C: - reg:1
!b|!c|

http://www.bkjia.com/PHPjc/532387.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/532387.htmlTechArticleIn PHP, there are many discussions about session. In fact, there are several functions in PHP4 that we usually don’t pay attention to. Arrived. Let me introduce them to you below. Among them, session_set_save_...