PHP 学习 第一天

PHP的变量

1.必须是$开头

2.区分大小写

3.不能以数字开头（不算$）

单行注释

 // ……

多行注释

 /*

……

*/

 

1 <? php
2   // phpinfo();
3   $myarray = array ( " 1 " , " 2 " , " 3 " , " 4 " );
4   for ( $i = 0 ; $i < count ( $myarray ); $i ++ ){
5 echo $myarray [ $i ] . " <br> " ;
6 }
7 ?>
8 < hr >
9 <? php
10 $myarray = array ( ' aaa ' => ' 111 ' , ' bbb ' => ' 222 ' );
11 echo $myarray [ ' aaa ' ];
12 ?>
13 < hr >
14 <? php
15 $aa = 11 ;
16 $bb = " 22 " ;
17 $aa += (int) $bb ;
18 echo $aa ;
19 ?>
20 < hr >
21 <? php
22 $aa = " 1234567890 " ;
23 echo substr ( $aa , 0 , 5 ) . " <br /> " ;
24 echo is_string ( $aa ) . " <br /> " ;
25 echo is_int ( $aa ) . " <br /> " ;
26 ?>
27 < hr >
28 <? php
29 echo $_SERVER [ " PHP_SELF " ] . " <br /> " ;
30 echo $_SERVER [ " SERVER_PORT " ] . " <br /> " ;
31
32
33 echo $_SERVER [ " HTTP_REFERER " ] . " <br /> " ; // =http://localhost/lianxi/
34 echo $_SERVER [ " HTTP_ACCEPT_LANGUAGE " ] . " <br /> " ; // =zh-cn
35 echo $_SERVER [ " HTTP_ACCEPT_ENCODING " ] . " <br /> " ; // =gzip, deflate
36 echo $_SERVER [ " HTTP_USER_AGENT " ] . " <br /> " ; // =Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727)
37 echo $_SERVER [ " HTTP_HOST " ] . " <br /> " ; // =localhost
38 echo $_SERVER [ " HTTP_CONNECTION " ] . " <br /> " ; // =Keep-Alive
39 echo $_SERVER [ " PATH " ] . " <br /> " ; // =C:WINDOWSsystem32;C:WINDOWS;C:WINDOWSSystem32Wbem;C:Program FilesCommon FilesAdobeAGL;C:Program FilesMySQLMySQL Server 5.0bin;C:php;C:phpext
40 echo $_SERVER [ " SystemRoot " ] . " <br /> " ; // =C:WINDOWS
41 echo $_SERVER [ " COMSPEC " ] . " <br /> " ; // =C:WINDOWSsystem32cmd.exe
42 echo $_SERVER [ " PATHEXT " ] . " <br /> " ; // =.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH
43 echo $_SERVER [ " WINDIR " ] . " <br /> " ; // =C:WINDOWS
44 echo $_SERVER [ " SERVER_SIGNATURE " ] . " <br /> " ; // =
45
46 echo $_SERVER [ " SERVER_SOFTWARE " ] . " <br /> " ; // =Apache/2.0.55 (Win32) PHP/5.1.1
47 echo $_SERVER [ " SERVER_NAME " ] . " <br /> " ; // =localhost 服务器名称
48 echo $_SERVER [ " SERVER_ADDR " ] . " <br /> " ; // =127.0.0.1
49 echo $_SERVER [ " SERVER_PORT " ] . " <br /> " ; // =80 服务器端口
50 echo $_SERVER [ " REMOTE_ADDR " ] . " <br /> " ; // =127.0.0.1
51 echo $_SERVER [ " DOCUMENT_ROOT " ] . " <br /> " ; // =D:/lianxi 网站的主目录
52 echo $_SERVER [ " SERVER_ADMIN " ] . " <br /> " ; // =sss@163.com 安装APACHE时设置的邮箱
53 echo $_SERVER [ " SCRIPT_FILENAME " ] . " <br /> " ; // =D:/lianxi/lianxi/servervalues.php 当前的网页的绝对路径，
54 echo $_SERVER [ " REMOTE_PORT " ] . " <br /> " ; // =1076 远程端口
55 echo $_SERVER [ " GATEWAY_INTERFACE " ] . " <br /> " ; // =CGI/1.1
56 echo $_SERVER [ " SERVER_PROTOCOL " ] . " <br /> " ; // =HTTP/1.1
57 echo $_SERVER [ " REQUEST_METHOD " ] . " <br /> " ; // =GET
58 echo $_SERVER [ " QUERY_STRING " ] . " <br /> " ; // =获取？号后面的内容
59 echo $_SERVER [ " REQUEST_URI " ] . " <br /> " ; // =例子：/lianxi/servervalues.php?a=1&b=2
60 echo $_SERVER [ " SCRIPT_NAME " ] . " <br /> " ; // =例子：/lianxi/servervalues.php
61 echo $_SERVER [ " PHP_SELF " ] . " <br /> " ; // =/lianxi/servervalues.php 返回当前网页的相对路径.
62 echo $_SERVER [ " REQUEST_TIME " ] . " <br /> " ; // =1179190013 运行时间 单位为十万分之一毫秒
63 echo $_SERVER [ " argv " ] . " <br /> " ; // =Array
64 echo $_SERVER [ " argc " ] . " <br /> " ; // =0
65 /*
66 1，$_SERVER["QUERY_STRING"]
67 说明：查询(query)的字符串
68 2，$_SERVER["REQUEST_URI"]
69 说明：访问此页面所需的URI
70 3，$_SERVER["SCRIPT_NAME"]
71 说明：包含当前脚本的路径
72 4，$_SERVER["PHP_SELF"]
73 说明：当前正在执行脚本的文件名
74 实例：
75 */
76
77 echo $_SERVER [ " QUERY_STRING " ] . " <br /> " ; // = “”
78 echo $_SERVER [ " REQUEST_URI " ] . " <br /> " ; // = “/”
79 echo $_SERVER [ " SCRIPT_NAME " ] . " <br /> " ; // = “/index.php”
80 echo $_SERVER [ " PHP_SELF " ] . " <br /> " ; // = “/index.php”
81
82
83
84 echo $_SERVER [ " QUERY_STRING " ] . " <br /> " ; // = “p=222〃
85 echo $_SERVER [ " REQUEST_URI " ] . " <br /> " ; // = “/?p=222〃
86 echo $_SERVER [ " SCRIPT_NAME " ] . " <br /> " ; // = “/index.php”
87 echo $_SERVER [ " PHP_SELF " ] . " <br /> " ; // = “/index.php”
88
89
90
91 echo $_SERVER [ " QUERY_STRING " ] . " <br /> " ; // = “p=222&q=baidu”
92 echo $_SERVER [ " REQUEST_URI " ] . " <br /> " ; // = “/index.php?p=222&q=baidu”
93 echo $_SERVER [ " SCRIPT_NAME " ] . " <br /> " ; // = “/index.php”
94 echo $_SERVER [ " PHP_SELF " ] . " <br /> " ; // = “/index.php”
95 echo $_SERVER [ " QUERY_STRING " ] . " <br /> " ; // 获取查询语句，实例中可知，获取的是?后面的值
96 echo $_SERVER [ " REQUEST_URI " ] . " <br /> " ; // 获取http://www.baidu.com后面的值，包括/
97 echo $_SERVER [ " SCRIPT_NAME " ] . " <br /> " ; // 获取当前脚本的路径，如：index.php
98 echo $_SERVER [ " PHP_SELF " ] . " <br /> " ; // 当前正在执行脚本的文件名
99
100
101 ?>

 

 

相关文件：

http://files.cnblogs.com/xiaobei/php001.zip

转载于:https://www.cnblogs.com/xiaobei/archive/2010/11/16/1878472.html