刚用PHP写了一个网站在线人数的程序，请大家进来指点下！!G+e7S:c)u!|8M-o
我是用PHP+MYSQL来写的，原理：网站在线人数的程序代码+后台有MYSQL数据库支持，可以直接统计出网站当前的在线人数。.E)B9[.g.E%s.Y6X1Q
首先我创建MYSQL数据库表。
7`7z0\*~*K0[6U:h2s!]CREATE TABLE tablename (
7r&n!W5o)`%|0Htech.techweb.com.cnfield type(max_length) DEFAULT 'default_value' (NOT) NULL
.c9F*~0X8R'Z:_5j}可以使用的SQL语句。
.D/h)Z:{5@8u)Ktech.techweb.com.cnCREATE TABLE useronline (
5R1@,Q-[:s e#I4a9A7]tech.techweb.com.cntimestamp int(15) DEFAULT '0' NOT NULL,
'S/H'C'A$I+?:j8p!?程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛ip varchar(40) NOT NULL,
-V U+}&e)a1q!g)Yfile varchar(100) NOT NULL,4L6_)U*T'P2o%]
PRIMARY KEY (timestamp),
4g/|+\-H/L)M8\TechWeb-技术社区KEY ip (ip),TechWeb-技术社区%R*l-X4y'V'a0m
KEY file (file)程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛9h,]"|+v4?(w+l%a
);下面我们是PHP脚本，首先我定义MYSQL的信息。
.g%E$J'g6v,L0Y程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛$server = "localhost"; //你的服务器3Y/L2z,L)|+F6^
$db_user = "root"; //你的mysql的用户名
)g4?&}%~,K程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛$db_pass = "password"; //你的mysql的密码7\6m%k:^*t+^'T.[&d
$database = "users"; //表的名字设置统计的时间(多少秒内在线人数)TechWeb-技术社区-\%Q$w6l:X
$timeoutseconds = 300;取当前时间。TechWeb-技术社区-`9c+`&S'Z.U8v5M
$timestamp = time();上面的完整代码：
9G6V!?+I)M-e程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛<?php9K&o"A/i0I:Q
$server = "localhost"; //your server
3Q'w,P6W9l+q-`2T-K程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛$db_user = "root"; //your mysql database username8{0q"L2O/k-Y$d
$db_pass = "password"; //your mysql database password if any
:g5m5M/P!H r5^%d$database = "users"; //the db name
(?-e2~*~!{+k5e.B etech.techweb.com.cn$timeoutseconds = 300;//timeoutseconds limit
3`)V%z-o$v,t%M+Otech.techweb.com.cn//get the current time
#_;])E8F5S,qTechWeb-技术社区$timestamp = time();程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛&T Y S I'D-K9_"X8^:S(F
//calculate the lowest timestamp allowed
&]6c(p9r Q0r"T3J.k'i6Vtech.techweb.com.cn$timeout = $timestamp-$timeoutseconds;tech.techweb.com.cn2h/Y4B;N.J8I,L&H
?>连接mysql"x/N0`.f,L"I.N+{3O.j
mysql_connect('localhost', 'username', 'password');也允许使用变量形式。
.a+A2c;k(Z,?'Amysql_connect($server, $db_user, $db_pass);如果mysql数据库没有密码的话可以使用下面代码连接
#{8X7D*?.c+`$cmysql_connect($server, $db_user);查询数据库的代码：4X3r;Y0d2t0z6V1r w,_
mysql_db_query('database', 'query');我们只要有访客就要增加一条记录。
3E/z/?&B%G)r5o$insert = mysql_db_query($database, "INSERT INTO useronline VALUES6f6z7S'l.v8R!i1`
('$timestamp','".$_SERVER['REMOTE_ADDR']."','".$_SERVER['PHP_SELF']."')");TechWeb-技术社区$t*w"@/w*W&|+H0V
如果用户用错误信息的话，这样处理。tech.techweb.com.cn1v.x4C#]$Q3w1\
if(!($insert)) {/k,W4`2j#?4h1t(T!O/u%c(]
print "Useronline Insert Failed > ";
7z9{!i;m8C"_0{}然后实现当超过设置的时间就删除该用户记录。;m4K5U2a"h1N!v&[8x N1u
$delete = mysql_db_query($database, "DELETE FROM useronline WHERE timestamp<$timeout");同样给出删除记录出错的处理。tech.techweb.com.cn4y)f.E K8g']%Y
if(!($delete)) {tech.techweb.com.cn5K%B0E%d4{5p.`,H3X&B
print "Useronline Delete Failed > ";
&R)t'm+u#w%T+i(o$p8x2]程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛}下面我们解决数据库中不同IP的问题程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛%J6O*_-N;|6F
$result = mysql_db_query($database, "SELECT DISTINCT ip FROM useronline WHERE file='".$_SERVER['PHP_SELF']."' ");使用)G'X)[*k*I!a/T#z(N
mysql_num_rows(query);来统计用户，代码如下。
-f'F6I6W$V#n+@#atech.techweb.com.cn$user = mysql_num_rows($result);最后关闭数据库。程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛)Z3x)a(q'N']+Q0J$]
mysql_close();显示在线的人数。
$o2N3c)k.z C.\ nif($user == 1) {%N:u+g&f-A.e2p6|2D
print("1 user online\n");程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛 p5I,X4U9z.y
} else {TechWeb-技术社区4S(z'p3{9I,p's
print("$user users online\n");
"{4L%t X)P#T0v9d}最终把上面代码写成一个PHP文件如下。
$F0}:Y*n;~'U$w:`4A j5{/\<?phpTechWeb-技术社区0n$I&~)K*i4i$A
//Put your basic server info here!b/a*Z&q1K6K
$server = "localhost"; //normally localhost
-P6M,q0| L%z#v$k ^/q#F8]$db_user = "root"; //your MySQL database usernametech.techweb.com.cn/G6U.i3F(f(F$B r2Y
$db_pass = "password"; //your MySQL database password
3n7k;H {:j.k*l)d5_1p$database = "users";
)Z'L6q*{#J#V程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛$timeoutseconds = 300; //it will delete all people which haven't refreshed(so probbably are
$C7]0G7k1Z U3}/L)d)k)c:A gTechWeb-技术社区// offline or inactive) in $timieoutseconds time (so it actually checks the people that are active in the last
5w0\4W!K.~-[)d'y;Q程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛// $timeoutseconds seconds)
$z4O$Y.v#L2\4I*s//this is where PHP gets the time
7@7K&B+m4a/tTechWeb-技术社区$timestamp = time();TechWeb-技术社区-r&H6u2y-W [8J5l6@0H
//counts the timeout, all people which have been seen last online in earlier than this timestamp, will get removed程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛)E;?2o9~3V
$timeout = $timestamp-$timeoutseconds;
6[;N9N5Z(p-t+I3~2J%Dtech.techweb.com.cn//connect to database
-{2U4k;t;o e$ytech.techweb.com.cnmysql_connect($server, $db_user);TechWeb-技术社区"{0W4N$p"V.h
//add the timestamp from the user to the online list
(X(k)^9\&M&I'S)q3\)utech.techweb.com.cn$insert = mysql_db_query($database, "INSERT INTO useronline VALUES,A,g)V,I$i.Z"J*]/W Y.w
('$timestamp','".$_SERVER['REMOTE_ADDR']."','".$_SERVER['PHP_SELF']."')");
2d*H2c0V)i,T'T0X程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛if(!($insert)) {程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛!y(B&Q!b2K#L._!E#x(X#V%b
print "Useronline Insert Failed > ";TechWeb-技术社区7~9M2q-y"J1p(z,M&K
}
,b6j-M$g-q2Wtech.techweb.com.cn//delete the peoples which haven't been online/active in the last $timeoutseconds seconds.TechWeb-技术社区6\#K/g.l2T%L-E-R*J:_
$delete = mysql_db_query($database, "DELETE FROM useronline WHERE timestamp<$timeout");"?(d6~(f&V n1m
if(!($delete)) {
!?7O)n&X;p&D4k*N0Lprint "Useronline Delete Failed > ";*y"?/\9`"e2S;B1q5K ~
}
-H7q8W:C-j']&m)i//select the amount of people online, all uniques, which are online on THIS page
/f)b'q({3H$C+`tech.techweb.com.cn$result = mysql_db_query($database, "SELECT DISTINCT ip FROM useronline WHERE file='".$_SERVER['PHP_SELF']."' ");TechWeb-技术社区#?5A(J"x6F
if(!($result)) {
6Z6?;u5l"@ G/E*Iprint "Useronline Select Error > ";'Z&x$G1B)^-Q"G8a1c%H
}
6U b#C%A8z1T0@1n//Count the number of rows = the number of people online5s1v6?9}&h)\0t&v&@
$user = mysql_num_rows($result);
,[3X2O:M0N!c//spit out the results5U%r0x#A0I$F)\0Z7u
mysql_close();TechWeb-技术社区2h9O.`(g$M&l6?
if($user == 1) {
'S7z!o:m)[)K;]程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛print("1 user online\n");,O+o#L&V9o5S9q:C-h
} else {程序开发，操作系统，服务器，源码下载，Linux,Unix,BSD,PHP,Apach,asp,下载,源码,黑客,安全,技术社区,技术论坛.v)|&w-R,^0~
print("$user users online\n");
&H:j+J-Z(S1t,?#q}
-\'z;Q:e!_8N6s*L$k?>