<?php
function getExt($filename){
$ext=strtolower(pathinfo($filename,PATHINFO_EXTENSION));
return $ext;
}
echo getExt('1.txt.html.pHP');//php
echo '<br/>';
$filename='3.html';
echo getExt($filename);//html
?>
函數(shù)作用域
局部變量--動態(tài)變量
<?php
function test1(){
$i=1;
$j=2;
return $i+$j;
}
var_dump(test1());//int 3
var_dump($i,$j);//報錯
?>
<?php
$m = 3;
$n = 4;
function test()
{
var_dump($m, $n);//報錯
}
test();
?>
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局部變量-動態(tài)變量
function test()
{
$i=1;
echo $i."<br/>";
++$i;
}
test();//1
test();//1
局部變量-動態(tài)變量
function test()
{
static $i=1;
echo $i."<br/>";
$i++;
}
test();//1
test();//2
var_dump($i);//報錯
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global關(guān)鍵字
$i = 1;
$j = 2;
function test2()
{
//global $i;
//global $j;
global $i, $j;
var_dump($i, $j);//int 1 int 2
$i = 3;
$i = 5;
}
test2();
var_dump($i, $j);//int 5 int 2
global不能賦值
function test()
{
//global $m=3;//報錯
global $m, $n;
$m = 3;
$n = 5;
}
test();
var_dump($m, $n);//int 3 int 5
$GLOBAL
$username = 'king';
$age = 12;
$i = 11;
//print_r($GLOBALS);
//.....
//(...
//[username] => king
//[age] => 12
// [i] => 11
function test()
{
echo '用戶名為' . $GLOBALS['username'] . "<br/>";//用戶名為king
$GLOBALS['age'] = 22;
}
test();
var_dump($age);//int 22
Array
(
[GLOBALS] => Array
*RECURSION*
[_POST] => Array
(
)
[_GET] => Array
(
)
[_COOKIE] => Array
(
)
[_FILES] => Array
(
)
[_ENV] => Array
(
)
[_REQUEST] => Array
(
)
[_SERVER] => Array
(
[HTTP_HOST] => 127.0.0.1
[HTTP_CONNECTION] => keep-alive
[HTTP_CACHE_CONTROL] => max-age=0
[HTTP_ACCEPT] => text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
[HTTP_UPGRADE_INSECURE_REQUESTS] => 1
[HTTP_USER_AGENT] => Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.101 Safari/537.36
[HTTP_ACCEPT_ENCODING] => gzip, deflate, sdch
[HTTP_ACCEPT_LANGUAGE] => zh-CN,zh;q=0.8
[PATH] => C:\ProgramData\Oracle\Java\javapath;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit\;D:\Program Files\Git\cmd;C:\Program Files (x86)\Microsoft SQL Server\90\Tools\binn\;C:\Program Files\TortoiseSVN\bin;C:\Program Files\nodejs\;D:\Program Files\mysql-5.7.18-winx64\bin;C:\WINDOWS\system32\config\systemprofile\AppData\Local\Microsoft\WindowsApps
[SystemRoot] => C:\WINDOWS
[COMSPEC] => C:\WINDOWS\system32\cmd.exe
[PATHEXT] => .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
[WINDIR] => C:\WINDOWS
[SERVER_SIGNATURE] =>
[SERVER_SOFTWARE] => Apache/2.2.21 (Win32) PHP/5.3.10
[SERVER_NAME] => 127.0.0.1
[SERVER_ADDR] => 127.0.0.1
[SERVER_PORT] => 80
[REMOTE_ADDR] => 127.0.0.1
[DOCUMENT_ROOT] => C:/wamp/www/
[SERVER_ADMIN] => admin@localhost
[SCRIPT_FILENAME] => C:/wamp/www/testClass/test1.php
[REMOTE_PORT] => 3929
[GATEWAY_INTERFACE] => CGI/1.1
[SERVER_PROTOCOL] => HTTP/1.1
[REQUEST_METHOD] => GET
[QUERY_STRING] =>
[REQUEST_URI] => /testClass/test1.php
[SCRIPT_NAME] => /testClass/test1.php
[PHP_SELF] => /testClass/test1.php
[REQUEST_TIME] => 1502890255
)
[username] => king
[age] => 12
[i] => 11
)
