PHP Arrays
An array is a type of special variable in PHP. It stores multiple elements/items of the same data type in a single variable. So that does not need to declare any other variable for each data. With this, it creates a list of items/elements of a similar data type that can be accessed using its index/key.
Note: You can define array in PHP by using PHP array function " array( ); " and square bracket " [ ] ".
Example: The following Example of An array in PHP.
$tutorial = array( "PHP", "PYTHON", "NODE JS");
OR
$tutorial = [ "PHP", "PYTHON", "NODE JS" ];
Let's create an array in PHP:
<!DOCTYPE html>
<html>
<body>
<?php
$tutorial = [ "PHP", "PYTHON", "NODE JS" ];
// Print array
Print_r($tutorial);
echo "<br>";
//Access the array value by key
echo $tutorial[0] ."<br>";
echo $tutorial[1] ."<br>";
echo $tutorial[2] ."<br>";
?>
</body>
</html>
According to Example, " $tutorial " it is a variable In which "PHP", "PYTHON", "NODE JS" elements are stored.
Parameter of An Array
| 1. |
Key |
Defines the key Numeric / String. |
| 2. |
Value |
Defines the value. |
Advantages of PHP array
- Less Code.
- Easy to traverse.
- Sorting.
There are three types of the array in PHP
- PHP Indexed Arrays
- PHP Associative Arrays
- PHP Multidimensional Arrays
PHP Indexed Arrays
PHP Indexed Array is used to hold any type of item/element. In Array, index/key will be represented by a number. By default, PHP indexed array begins with 0. it is also known as a numeric array.
Syntax of PHP Indexed Array
array(value1, value2, value3);
Examples: The following Examples for understanding PHP Indexed Arrays.
1. Access PHP Indexed Array
<!DOCTYPE html>
<html>
<body>
<?php
$source = array("welcome","to","w3alert.com");
echo $source[0] ." ". $source[1] ." ". $source[2] . "."; // keys are 0,1,2
?>
</body>
</html>
2. PHP Indexed Array with for Loop
<!DOCTYPE html>
<html>
<body>
<?php
$books = array( "Wings of Fire","The Secret","War and Peace");
$arrlen=count($books); // count the array length
for( $m = 0; $m < $arrlen; $m++ ) {
echo $books[$m];
echo "<br>";
}
?>
</body>
</html>
PHP Associative Arrays
The associative array is similar to the indexed array. Associative arrays are held elements or values in key-value pairs.
The array whose keys reside in string form is called array association array.
Syntax of PHP Associative Array
array("key1"=>"value1", "key2"=>"value2", "key"=>"value3");
Examples: The following Examples for understanding PHP Associative Arrays.
1. Access PHP Associative Array
<!DOCTYPE html>
<html>
<body>
<?php
$laptop_price = array( "Dell Vostro" => "25995","HP Notebook" => "21290","Lenovo Ideapad" => "27990" );
echo "The Price of Dell Vostro:"." ". $laptop_price['Dell Vostro'] ."<br>";
echo "The Price of HP Notebook:"." ". $laptop_price['HP Notebook'] ."<br>";
echo "The Price of Lenovo Ideapad:"." ". $laptop_price['Dell Vostro'] ."<br>";
?>
</body>
</html>
2. PHP Associative Array with for Loop
<!DOCTYPE html>
<html>
<body>
<?php
$old_year = array("Gretel"=>"20","Elizabeth"=>"24");
$keys = array_keys($old_year);
$arrlength = count($old_year);
for($l=0; $l < $arrlength; $l++) {
echo $keys[$l] . ' ' . $old_year[$keys[$l]] . "\n";
}
?>
</body>
</html>
3. PHP Associative Array with forEach Loop
<!DOCTYPE html>
<html>
<body>
<?php
$laptop_price = array( "Dell Vostro" => "25995","HP Notebook" => "21290","Lenovo ideapad" => "27990" );
foreach($laptop_price as $m => $m_value) {
echo "Key=" . $m . ", Value=" . $m_value;
echo "<br>";
}
?>
</body>
</html>
PHP Multidimensional Arrays
PHP Multidimensional array is used to store more than one arrays. Each element in the array holds the other sub-arrays. PHP Multidimensional array has multiple indexes to access the sub-array.
Syntax of PHP Multidimensional Array
array (
array ( value1, value2, value3 ),
array ( value1, value2, value3 ),
);
Examples: The following Examples for understanding PHP Multidimensional Arrays.
1. Access PHP Multidimensional Array
<!DOCTYPE html>
<html>
<body>
<?php
// create PHP Multidimensional Array
$info = array
(
array("name"=>"John","age"=>"23","specialist"=>"PHP"),
array("name"=>"Marco","age"=>"28","specialist"=>"PYTHON"),
array("name"=>"Devin","age"=>"32","specialist"=>"PHP,JAVA,PYTHON"),
);
// for Sub-array
print_r($info[0]);
echo "<br>";
print_r($info[1]);
echo "<br>";
print_r($info[2]);
echo "<br>";
// for Single Value
print_r($info[0]["name"]);
echo "<br>";
print_r($info[1]["name"]);
echo "<br>";
print_r($info[2]["name"]);
echo "<br>";
?>
</body>
</html>
2. PHP Multidimensional Array with forEach Loop
<!DOCTYPE html>
<html>
<body>
<?php
$info = array
(
array("name"=>"John","age"=>"23","specialist"=>"PHP"),
array("name"=>"Marco","age"=>"28","specialist"=>"PYTHON"),
array("name"=>"Devin","age"=>"32","specialist"=>"PHP,JAVA,PYTHON"),
);
foreach($info as $key => $value){
echo "<p><b> List $key Item</b></p>";
echo "<ul>";
foreach($value as $key1 => $value){
echo "<li>" .$key1. " = " .$value. "</li>";
}
echo "</ul>";
}
?>
</body>
</html>