PHP Backend Application(1)Env and PHP Knowledge

PHPBackendApplication(1)EnvandPHPKnowledge

CheckthePHPversion

>php--version

PHP5.6.16(cli)(built:Dec26201518:37:18)

Copyright(c)1997-2015ThePHPGroup

ZendEnginev2.6.0,Copyright(c)1998-2015ZendTechnologies

withZendOPcachev7.0.6-dev,Copyright(c)1999-2015,byZendTechnologies

withXdebugv2.2.5,Copyright(c)2002-2014,byDerickRethans

ThecommentsstyleissimilartoJava,filestarterandendarelikethis

<?php

echo"phprunsfirst!";

echo"\nrecallmyphpknowledge";//onelinecomments

/*

thisishowthcommentsgoinjava

*/

?>

Types

Fourscalartype:boolean,integer,float,string

Twocompoundtypes:array,object

Twospecialtypes:resource,NULL

Checkthetypeandgettype

<?php

$a_boolean=TRUE;

$a_string="foo";

echogettype($a_boolean);

echo"\n";

echovar_dump($a_string);

echois_string($a_string);

echo"\n";

?>

consoleoutputisasfollow:

boolean

string(3)"foo"

1

Castothervaluetoboolean

var_dump((bool)1);//bool(true)

var_dump((bool)-2);//bool(true)

Automaticallycoverttheinttofloat

$large_number=2147483647;

var_dump($large_number);//int(2147483647)

$large_number=2147483648;

var_dump($large_number);//float(2147483648)

SingleQuotedforString

//Outputs:Thiswillnotexpand:\nanewline

echo'Thiswillnotexpand:\nanewline';

//Outputs:Variablesdonot$expand$either

echo'Variablesdonot$expand$either';

DoubleQuoted

Heredoc

$str=<<<EOD

Exampleofstring

spanningmultiplelines

usingheredocsyntax.

EOD;

nowdocissinglequotedheredoc

echo<<<'EOT'

Mynameis"$name".Iamprintingsome$foo->foo.

Now,Iamprintingsome{$foo->bar[1]}.

Thisshouldnotprintacapital'A':\x41

EOT;

EnvironmentandTypes

>cattype.php

<?php

$arr=array("foo"=>1,12=>true);

echogettype($arr[12])."\n";

echo$arr[12]."\n";

?>

>phptype.php

boolean

1

unset($arr[5]);//Thisremovestheelementfromthearray

unset($arr);//Thisdeletesthewholearray

Asmentionedabove,ifnokeyisspecified,themaximumoftheexistingintegerindicesistaken,andthenewkeywillbethatmaximumvalueplus1.

Theunset()functionallowsremovingkeysfromanarray.Beawarethatthearraywillnotbereindexed.

Thearray_values()functioncanbeusedto'removeandshift'.

$a=array(1=>'one',2=>'two',3=>'three');

unset($a[2]);

/*willproduceanarraythatwouldhavebeendefinedas

$a=array(1=>'one',3=>'three');

andNOT

$a=array(1=>'one',2=>'three');

*/

print_r($a);

echo"<br/>";

$b=array_values($a);

//Now$bisarray(0=>'one',1=>'three')

print_r($b);

CodeStandard

PHPwithFPM

PHPLumen

InstalllatestPHPonEC2

UNITTest

>phpunit--version

PHPUnit5.1.3bySebastianBergmannandcontributors.

References:

PHPBasic1~3

PHP1~8

LanguageReferences

http://php.net/manual/en/langref.php

PHPEnv