What is array

Array is collection of same data types. In PHP, an array stores multiple values in one single variable. I.e. an array is a special variable, which can store multiple values in one single variable.

using PHP, there are three types of array.

•  Numeric Array
•  Associative Array
• Multidimensional Array

Numeric Array:

A numeric array stores each array element with a numeric index. i.e.  When we create numeric array, index automatically or manually assigned for each value of array at creation time.

Define array:

    

$array_name = array (array_value1, array_value2,array_value3,array_value4,--------);

$array_name[0] = array_value0;

$array_name[1] = array_value1;

$array_name[2] = array_value2;

$array_name[3] = array_value3;

..........................

..........................

$array_name[N] = array_valuen; 

Associative Array:

An associative array, each ID key is associated with a arrayvalue. When storing data about specific named values, a numerical array is not always the best way to do it. With associative arrays we can use the values as keys and assign values to them

Syntax

$ass_array = array ( "index_Id1" => arrayvalue , "index_id1" => arrayvalue, .........);

// Declare  one- dimensional array

echo "<h3>"."This is one- dimensional array"."</h3>"."</br>";

$subject = array("Mathematics","MySQL","Physics","Chemistry","English","Sanskrit","PHP","Hindi","Geography","Civics","History","Economics","Political Science");

foreach($subject as $v)

echo $v."<br>";

or

for($i=0; $i<count($subject); $i++)

{

//print_r()

echo $subject[$i]."<br><br>";

}

// Declare two-dimensional array

       $matrix  = array

                     ( array (1,2,3),

                       array (4,5,6),

                       array (7,8,9),

    array (10,11,12)

                     );

 

  echo "<h3>"."This is two dimensional array"."</h3>"."</br>";

// Print two dimensional array element

       for($row = 0; $row<4; $row++)

        {

           for($col = 0; $col<4;  $col++)

             {

                echo $matrix[$row][$col]."\t" ."\t ";

               }

               echo "</br>";

       }

//////////////////////////

Multi-dimensional array

An array can also contain another array as a value, which in turn can hold other arrays as well. In such a way we can create two- or three-dimensional arrays:

// Declare multi-dimensional array

$organization = array (array (array ("Tech","Vikash","Gupta"),

                             array  ("Sales","Sunal","Araoa"),

                             array  ("HR", "Sudhir","Aray")

                             ),

                       array (array  ("Tech","Minku","Jain"),

                             array  ("Salesteam","Guru","Gupta"),

                             array  ("HR", "Saurabh","Sharma")

                            )

                      );

echo "<h3>"."This is multidimensional Array"."</h3>"."</br>";

                    

for($layer=0; $layer<2; $layer++)

 {

  for($row=0; $row<3; $row++)

   {

    for($col=0; $col<3; $col++)

       {

        echo $organization[$layer][$row][$col]."\t";

       }

  echo "</br>" ;

 }

 echo "</br>";

 }

 ?>