PHP Array
—All the variables you have used have held only a single
value.
—Array variables are “special” because they can hold more than one value in one
single variable.
There
are three types of array:-
—Indexed array : An array with a
numeric index
—Associative array : An array where
each key is associated with a value
—Multidimensional array : An array
containing one or more array
How to define an array
FIRST
METHOD:-
<?php
$arr = array(10,11,12,13,14,15);
echo $arr[0];
?>
2nd
method
<?php
$arr[ ]=10;
$arr[ ]=20;
$arr[ ]=30;
$arr[ ]=40;
$arr[ ]=50;
echo
$arr[0];
?>
3rd
method
<?php
$arr[0]=10;
$arr[1]=20;
$arr[2]=30;
$arr[3]=40;
$arr[4]=50;
echo $arr[0];
?>
PHP Associative Array
—In associative array index( key ) can initialized
according to Your own requirement.
—An array in PHP is actually an ordered map. A map is a
type that associates values to keys.
—In this association use ( => ) sign to define index and values.
There are two ways to create an associative array
—First
Way to define associative Array
<?php
$Personage=array("Ravi"=>"30","Vishu"=>"21","Harmeet"=>"43");
echo "Ravi is
".$Personage["Ravi"]."Years old";
?>
—Another
Way to define associative Array
<?php
$Personage['Ravi']=30;
$Personage['Vishu']=21;
$Personage['Harmeet']=43;
echo "Harmeet is ".$Personage["Ravi"]."Years
old";
?>
Loop Through an Associative Array
<?php
$state=array("Dl"=>"Delhi","Hr"=>"Haryana","Pn"=>"Punjab","Br"=>"Bihar");
foreach($state as $val)
{
echo $val."
";
}
?>
Output
Delhi Haryana Punjab Bihar
Delhi Haryana Punjab Bihar
Using foreach display index(key) value of $state
array
<?php
$state=array("Dl"=>"Delhi","Hr"=>"Haryana","Pn"=>"Punjab","Br"=>"Bihar");
foreach($state as $key=>$val)
{
echo
$key."---".$val."<br/>";
}
?>
Output
Dl — Delhi
Hr — Haryana
Pn — Punjab
Br — Bihar
Dl — Delhi
Hr — Haryana
Pn — Punjab
Br — Bihar
PHP Indexed Array
PHP numeric array
—Numeric array can stores numbers, strings etc.
—Default array index will be represented by numbers.
—By default array index starts from 0
—In PHP array( ) is used to crate array.Inside this can pass
multiple values separated by comma( , )
Syntax:-
array(value1,value2..)
Example
<?php
$arr=array(10,20,30,40,50);
$col=array("red","green","blue","black");
//print first value of $arr and $col array
echo $arr[0];
echo $col[0];
?>
We can define array in three ways
<?php
$col=array("blue","red","green","white","pink");
//OR
$col[ ]="blue";
$col[ ]="red";
$col[
]="green";
//OR
$col[0]="blue";
$col[1]="red";
$col[2]="green";
?>
Loop Through an Numeric(Indexed) Array
Find the sum of given array
<?php
$sum=0;
$arr=array(10,20,30,40,50);
for($i=0;$i<count($arr);$i++)
{
$sum=$sum+$arr[$i];
}
echo "Sum of given array = ".$sum;
?>
Display all the colors name i.e stored in array
<?php
$col=array("blue","red","green","white","pink");
for($i=0;$i<count($col);$i++)
{
echo $col[$i]." ";
}
?>
Find Sum of even and odd numbers stored in array
<?php
$arr=array(10,11,12,13,14,15);
for($i=0;$i<count($arr);$i++)
{
if($arr[$i]%2==0)
{ $even=$even+$arr[$i];
}
else
{ $odd=$odd+$arr[$i]; }
}
echo "Sum of even=".$even."<br/>";
echo "Sum of odd=".$odd;
?>
PHP Nested Array
Nested / Multi-dimensional Array
—A multidimensional
array is an array containing one or more arrays.
—The dimension of an
array indicates the number of indices you need to select an element.
—For a two-dimensional
array, you need two indices to select an element
—For a
three-dimensional array, you need three indices to select an element.
—Syntax
array(
array(val1, val1, val2..),
array(val1,val2,val3..)
);
Create a two dimensional numeric array and find the sum.
<?php
error_reporting(‘ERROR’);
$arr=array(array(10,10,10),array(10,10,10),array(10,10,10));
$s=0; $s1=0;
//using for loop:
for($i=0;$i<3;$i++)
{ for($j=0;$j<3;$j++)
{ echo $arr[$i][$j]." ";
$s=$s+$arr[$i][$j];
}
echo "<br>";
}
echo "sum of array:".$s;
?>
Create a two dimensional numeric array and find the sum
using for-each
<?php
error_reporting(‘ERROR’);
$arr=array(array(10,10,10),array(10,10,10),array(10,10,10));
$s=0; $s1=0;
//using foreach loop:
foreach($arr as $k)
{
foreach($k as $v)
{
echo
$v;
$s1=$s1+$v;
}
echo "<br>";
}
echo "sum of array:".$s;
?>
More Examples
—Two
dimensional associative array( user’s name and mobile number)
—Two
dimensional associative array
Multidimensional associative array
—Syntax
array(
array(
array(
array(val1, val1, val2....)
)
)
);