PHP Developer''''s Dictionary- P25 ppsx

array_walk Syntax int array_walkarray arr, string func, mixed userdata Description The array_walk function , which was added in PHP 3.0.3 and PHP 4.0, executes the function func with

The array_values() function returns all the values (not keys) of the input array

array_walk()

Syntax

int array_walk(array arr, string func, mixed userdata)

Description

The array_walk() function , which was added in PHP 3.0.3 and PHP 4.0, executes the function func with each element in the array Each func call will have the array

value as the first parameter and the array key as the second parameter When

userdata is present, it will be passed as the third parameter to func Note that

when func encounters errors, a warning will be generated each time To suppress

these warnings, call array_walk() with an @ sign in front of it Also, array_walk() doesn't reset the array by default, so you might need to call reset() between subsequent calls of array_walk()

arsort()

Syntax

void arsort(array array)

Description

The arsort() function sorts the array in reverse order, based on the values in the

array with the corresponding indices (keys) being maintained

$array1 = array("c"=>"1","b"=>"2","a"=>"3");

arsort($array1);//array1 = ("a"=>"3","b"=>"2","c"=>"1")

asort()

Syntax

void asort(array array)

The asort() function sorts the array based on the values in the array with the corresponding indices (keys) being maintained

$array1 = array("a"=>"3","b"=>"2","c"=>"1");

asort($array1);//array1 = ("c"=>"1","b"=>"2","a"=>"3")

compact()

Syntax

array compact(string varname | array varnames, [ ] )

Description

The array_compact() function, which was added in PHP 4.0, takes both names of variables and arrays that contain the names of variables, and looks up these variable names in the current symbol table Each variable name becomes a key and the variable's content becomes the value for a new array, which is created and returned

count()

Syntax

int count(mixed var)

Description

The count() function returns the number of elements in var which is typically an

array If var is not an array, the function will return 1; if var is not set, count() will return 0

current()

Syntax

mixed current(array array)

Description

The current() function returns the element in array that is currently being pointed

to by an internal pointer Every array has this internal pointer, which is initialized to point to the first element of the array If the internal pointer points beyond the element list, the function returns false

each()

Syntax

array each(array array)

Description

The each() function returns the current key and value pair from array and advances

the internal pointer to the next key and value pair The return array consists of four elements, where the elements are comprised of the keys: 0, 1, key, and value

Elements 0 and key contain the key name of the current array element, and 1 and

value contain the data If the internal pointer for array extends past the end of

array 's contents, each() returns false

end()

Syntax

end(array array)

Description

The end() function moves the internal pointer for array to the last element in array

extract()

Syntax

void extract(array var_array, int [extract_type] , string [prefix] )

Description

The extract() function, which was added in PHP 3.0.7 and PHP 4.0, imports

takes its keys as variable names and its values as the corresponding variable values Each key/value pair will result in one new entry in the symbol table In the case where a collision occurs (the variable already exists in the symbol table), the

extract_type is taken into consideration The possible values for extract_type are

EXTR_OVERWRITE—Results in existing variables being overwritten

EXTR_SKIP—Results in the existing variable value being preserved in

the symbol table

EXTR_PREFIX_SAME—Results in the new variable being inserted into the

symbol table with prefix prepended to the variable name

EXTR_PREFIX_ALL—Results in all new variables in the symbol table

being prefixed with prefix

prefix defaults to EXTR_OVERWRITE EXTR_OVERWRITE and EXTR_SKIP don't require a specified prefix value

in_array()

Syntax

bool in_array(mixed needle, array haystack)

Description

The in_array() function, which was added in PHP 4.0, searches for needle in

haystack and returns true if the needle is found

$array1 = array(1,2,3,4,5);

echo in_array(3,$array1);//displays 1

key()

Syntax

mixed key(array array)

Description

The key() function returns the index element of the current array position that is

pointed to by the internal pointer

krsort()

Syntax

int krsort(array array)

Description

The krsort() function, which was added in PHP 3.0.13 and PHP 4.0, sorts the array

in reverse order based on the keys Key and value pairs are maintained

$array1 = array("a"=>"3","b"=>"2","c"=>"1");

krsort($array1);//array1 = ("c"=>"1","b"=>"2","a"=>"3")

ksort()

Syntax

int ksort(array array)

Description

The ksort() function sorts the array based on the keys Key and value pairs are

maintained

$array1 = array("c"=>"1","b"=>"2","a"=>"3");

ksort($array1);//array1 = ("a"=>"3","b"=>"2","c"=>"1")

list()

Syntax

void list( )

Description