session|函數(shù)

if (!isset($__session_inc__)){
$__session_inc__=1;
//require("cookie.inc.php3");
# -------------------------------------------------------------------
# Session Management v1.0 21.6.1998
# (c) Wild Karl Heinz
#
# This Include handle Session based variable handling
#
# Please feel free and use it. If you make it more functional
# it would be nice to send me a copy.
#
# Don't forget - Mysql_connect !
#
# The database structure
# Table structure for table 'session'
#
#??CREATE TABLE session (
#????id int(11) DEFAULT '0' NOT NULL auto_increment,
#????sid varchar(20) DEFAULT '' NOT NULL,
#????val blob,
#????times timestamp(14),
#????PRIMARY KEY (id),
#????KEY sid (sid),
#????UNIQUE sid_2 (sid)
#??);
#
# You'll miss here a cron job to delete the old sessions from db
# -------------------------------------------------------------------

// 請注意上面被注釋掉的CREATE TABLE語句，
// 你需要在你所使用的數(shù)據(jù)庫上執(zhí)行這條語句，
// 表名也可以不是session，那么就需要設置下面的$sess_table變量了。

// 此處你需要設置庫名，和表名。
// 不過一般建議就使用session作為表名
???$sess_db = 'dbname';
???$sess_table = 'session';
???
# ----------------------------------------------------
# Session_CheckID - 檢查、設置并返回 Session-ID
# 參數(shù)......: cookie保存時間(以分鐘計)
#?????????????也可不設置表示這個 cookie 只在當前session 有效
#?????????????這其實就象ASP中SESSION的時效一樣。
# 返回值....: 一個唯一的Session-ID （作為cookie存儲）
# ----------------------------------------------------
function Session_CheckID( $min )
{
????global $sess_sid;

????if( !$sess_sid ) {
??????$sess_sid = uniqid( SC ); //取得一個唯一的隨機數(shù)
/*
??????if( $min > 0 ) {
?????????SetCookie("sess_sid", $sess_sid, time()+($min*60), "/", "", 0 );
?????????}
??????else {
?????????SetCookie("sess_sid", $sess_sid, "", "/", "", 0 );
?????????}
上面是原先的代碼，會出錯。所以另外用了一個更好的函數(shù)。
函數(shù)庫：cookie.inc.php3
*/
????????jssetcookie("sess_sid",$sess_sid,$min);
??????return( false );
??????}
???else {
??????return( true );
??????}
}

# ----------------------------------------------------------
# str2arr - 將字符串轉換成session數(shù)組
# 參數(shù).....: string
# 返回值...: 全局數(shù)組（其實就是session)
#本函數(shù)用途：將字符串轉換成session數(shù)組
#如"session[username]=yourid&session[userpass]=12345"
#將會被轉換成下面的數(shù)組
#??session[username]="yourid"
#??session[userpass]="12345"
#請注意函數(shù)split(),each(),list(),eval()的用法。
# ----------------------------------------------------------
function str2arr( $ts )
{
???global $session;

???$vals = split( "&", $ts );
???while( list($key,$val) = each($vals) ) {
??????list( $name, $wert ) = split( "=", $val );
??????if( $val ) eval( "\$$name = \"$wert\";" );
??????}
}

# ----------------------------------------------------------
# session_read() - 從SESSION表中取數(shù)據(jù)，轉換成session數(shù)組
# 參數(shù)........: 無
# 返回值......: 如果讀出數(shù)據(jù)，返回 true ，否則返回 false
#注意.........: 用到了str2arr()這個函數(shù)
# ----------------------------------------------------------
function session_read()
{
???# Hash array to keep session-variables
???global $session;
???global $sess_sid, $sess_db, $sess_table, $sess_error;

???$sel = "Select val from $sess_table where sid = '$sess_sid'";
???$res = mysql_db_query( $sess_db, $sel );
???if( mysql_numrows( $res ) ) {
??????$val = mysql_result( $res, 0, "val" );
??????str2arr( $val );
??????mysql_free_result( $res );
??????return( true );
??????}
???else {
??????return( false );
??????$sess_error = mysql_error();
??????}
}

# ------------------------------------------------------
# Split_Array() - 將session數(shù)組轉換成字符串
# 參數(shù).......: 數(shù)組
# 返回值.....: 數(shù)組轉換得來的字符串
#
# Thanks to Rasmus (這人好象是PHP的發(fā)明人)
# 注意:將session數(shù)組轉換成字符串
#如session[username]="yourid"
#??session[userpass]="12345"
#將會被轉換成"session[username]=yourid&session[userpass]=12345"
#同時該函數(shù)考慮到了數(shù)組的某個元素也是數(shù)據(jù)的情況
#這個函數(shù)被設計成一個遞歸函數(shù)
# ------------------------------------------------------
function Split_Array( $arr, $a = "", $b = "", $c = "" )
{
???while( list( $key, $val ) = each( $arr ) ) {
??????if( is_array( $val ) ) {
?????????$ts .= Split_Array( $arr[ $key ],
??????????????????( strlen( $a ) ? $a : $key ),
??????????????????( strlen( $b ) ? $b : ( strlen( $a ) ? $key : "" ) ),
??????????????????( strlen( $c ) ? $c : ( strlen( $b ) ? $key : "" ) ) );
?????????}
??????else {
?????????$ts .= "session";
?????????$ts .= $a ? "[$a]" : "";
?????????$ts .= $b ? "[$b]" : "";
?????????$ts .= $c ? "[$c]" : "";
?????????$ts .= "[$key]=$val&";
?????????}
??????}
???return( $ts );
}

# ---------------------------------------------------
# session_write - 將session數(shù)組轉換成字符串，再存到session表中
# 參數(shù).: 無
# 返回值...: 如果存入正常返回 true ，否則返回??false
# ---------------------------------------------------
function session_write()
{
???# Hash array to keep session-variables
???global $session;

???global $sess_sid, $sess_db, $sess_table;
???global $sess_error;

???# if you like to delete a session-cookie
???# you must check it before writting the session
???# array

???if( !$sess_sid ) { session_checkid( 0 ); }

???$ts = Split_Array( $session );
???if( $ts > "" ) { $ts = substr( $ts, 0, strlen( $ts ) - 1 ); }
???$res??= mysql_db_query( $sess_db, "Select * from session where sid = '$sess_s'");
???if( mysql_numrows( $res ) == 0 ) {
??????$sel??= "Insert into $sess_table ( id, sid, val, times ) ";
??????$sel .= "values( 0, '$sess_sid', '$ts', NULL )";
??????}
???else {
??????$sel??= "Update $sess_table set val = '$ts', ";
??????$sel .= "times = NULL where sid = '$sess_sid'";
??????}
???if( !mysql_db_query( $sess_db, $sel ) ) {
??????$sess_error = mysql_error();
??????return( false );
??????}
???else { return( true ); }
}

# ---------------------------------------------
# session_del - 清除當前所有的session
#???????????????并刪除session表中和當前session有關的記錄
# 參數(shù).....: 一個隨機的session id
# 返回值...: 無
# ---------------------------------------------
function session_del()
{
???global $session, $sess_db, $sess_table, $sess_sid;

???$sel = "Delete from $sess_table where sid = '$sess_sid'";
???if( !mysql_db_query( $sess_db, $sel ) ) {
??????$sess_error = mysql_error();
??????}
???$sess_sid = '';
}
}
?>?