PHP

 

PHP

PHP: indicates the earliest version of PHP that supports the function.

PHP String Constants

PHP: indicates the earliest version of PHP that supports the constant.

Constant	Description	PHP
CRYPT_SALT_LENGTH	Contains the length of the default encryption method for the system. For standard DES encryption, the length is 2
CRYPT_STD_DES	Set to 1 if the standard DES-based encryption with a 2 character salt is supported, 0 otherwise
CRYPT_EXT_DES	Set to 1 if the extended DES-based encryption with a 9 character salt is supported, 0 otherwise
CRYPT_MD5	Set to 1 if the MD5 encryption with a 12 character salt starting with $1$ is supported, 0 otherwise
CRYPT_BLOWFISH	Set to 1 if the Blowfish encryption with a 16 character salt starting with $2$ or $2a$ is supported, 0 otherwise0
HTML_SPECIALCHARS
HTML_ENTITIES
ENT_COMPAT
ENT_QUOTES
ENT_NOQUOTES
CHAR_MAX
LC_CTYPE
LC_NUMERIC
LC_TIME
LC_COLLATE
LC_MONETARY
LC_ALL
LC_MESSAGES
STR_PAD_LEFT
STR_PAD_RIGHT
STR_PAD_BOTH

 

 

PHP Arithmetic Operators

Operator	Name	Description	Example	Result
x + y	Addition	Sum of x and y	2 + 2	4
x – y	Subtraction	Difference of x and y	5 – 2	3
x * y	Multiplication	Product of x and y	5 * 2	10
x / y	Division	Quotient of x and y	15 / 5	3
x % y	Modulus	Remainder of x divided by y	5 % 2 10 % 8 10 % 2	1 2 0
– x	Negation	Opposite of x	– 2
a . b	Concatenation	Concatenate two strings	"Hi" . "Ha"	HiHa

PHP Assignment Operators

The basic assignment operator in PHP is "=". It means that the left operand gets set to the value of the expression on the right. That is, the value of "$x = 5" is 5.

Assignment	Same as…	Description
x = y	x = y	The left operand gets set to the value of the expression on the right
x += y	x = x + y	Addition
x -= y	x = x – y	Subtraction
x *= y	x = x * y	Multiplication
x /= y	x = x / y	Division
x %= y	x = x % y	Modulus
a .= b	a = a . b	Concatenate two strings

PHP Incrementing/Decrementing Operators

Operator	Name	Description
++ x	Pre-increment	Increments x by one, then returns x
x ++	Post-increment	Returns x, then increments x by one
— x	Pre-decrement	Decrements x by one, then returns x
x —	Post-decrement	Returns x, then decrements x by one

PHP Comparison Operators

Comparison operators allows you to compare two values:

Operator	Name	Description	Example
x == y	Equal	True if x is equal to y	5==8 returns false
x === y	Identical	True if x is equal to y, and they are of same type	5==="5" returns false
x != y	Not equal	True if x is not equal to y	5!=8 returns true
x <> y	Not equal	True if x is not equal to y	5<>8 returns true
x !== y	Not identical	True if x is not equal to y, or they are not of same type	5!=="5" returns true
x > y	Greater than	True if x is greater than y	5>8 returns false
x < y	Less than	True if x is less than y	5<8 returns true
x >= y	Greater than or equal to	True if x is greater than or equal to y	5>=8 returns false
x <= y	Less than or equal to	True if x is less than or equal to y	5<=8 returns true

PHP Logical Operators

Operator	Name	Description	Example
x and y	And	True if both x and y are true	x=6 y=3 (x < 10 and y > 1) returns true
x or y	Or	True if either or both x and y are true	x=6 y=3 (x==6 or y==5) returns true
x xor y	Xor	True if either x or y is true, but not both	x=6 y=3 (x==6 xor y==3) returns false
x && y	And	True if both x and y are true	x=6 y=3 (x < 10 && y > 1) returns true
x || y	Or	True if either or both x and y are true	x=6 y=3 (x==5 || y==5) returns false
! x	Not	True if x is not true	x=6 y=3 !(x==y) returns true

PHP Array Operators

Operator	Name	Description
x + y	Union	Union of x and y
x == y	Equality	True if x and y have the same key/value pairs
x === y	Identity	True if x and y have the same key/value pairs in the same order and are of the same type
x != y	Inequality	True if x is not equal to y
x <> y	Inequality	True if x is not equal to y
x !== y	Non-identity	True if x is not identical to y

 

PHP – Multidimensional Arrays

A multidimensional array is an array containing one or more arrays.

In a multidimensional array, each element in the main array can also be an array. And each element in the sub-array can be an array, and so on.

Example

In this example we create a multidimensional array, with automatically assigned ID keys:

$families = array
  (
  "Griffin"=>array
  (
  "Peter",
  "Lois",
  "Megan"
  ),
  "Quagmire"=>array
  (
  "Glenn"
  ),
  "Brown"=>array
  (
  "Cleveland",
  "Loretta",
  "Junior"
  )
  );

The array above would look like this if written to the output:

Array
(
[Griffin] => Array
  (
  [0] => Peter
  [1] => Lois
  [2] => Megan
  )
[Quagmire] => Array
  (
  [0] => Glenn
  )
[Brown] => Array
  (
  [0] => Cleveland
  [1] => Loretta
  [2] => Junior
  )
)

Example 2

Lets try displaying a single value from the array above:

echo "Is " . $families[‘Griffin’][2] .
" a part of the Griffin family?";

The code above will output:

Is Megan a part of the Griffin family?