How to customize array in php

PHP is a widely used open source server-side scripting language. It is widely used in web development. An array in PHP is a special type of variable that can store multiple values. PHP provides many built-in array functions so that we can operate on data. But in some cases, the built-in functions cannot meet our needs and a custom array is required. This article will introduce how to customize an array in PHP.

1. Use the array() function to create

The easiest way to create an array is to use the array() function. This function can accept any number of parameters, each of which is in the array. an element.

For example:

$myArray = array("apple", "banana", "orange");

In this example, $myArray contains three elements, namely "apple", "banana" and "orange".

We can also specify subscripts for elements, for example:

$myArray = array("apple" => 2, "banana" => 3, "orange" => 5);

In this example, $myArray is an associative array, where the value of "apple" is 2 and the value of "banana" is 3, and the value of "orange" is 5.

2. Use the [] operator to create

In PHP5.4 and above, we can use the [] operator to create an array, as shown below:

$myArray = ["apple", "banana", "orange"];

The array created by this example is the same array created using the array() function.

At the same time, we can also use the [] operator to specify subscripts for array elements, for example:

$myArray = ["apple" => 2, "banana" => 3, "orange" => 5];

The array created in this example is the same as the associative array created using the array() function. .

3. Use the range() function to create

The range() function can create an array within a numerical range, for example:

$myArray = range(0, 10);

This example will create an array containing 0 An array of integers from 0 to 10, $myArray contains the following elements:

Array ( [0] => 0
        [1] => 1 
        [2] => 2 
        [3] => 3 
        [4] => 4 
        [5] => 5 
        [6] => 6 
        [7] => 7 
        [8] => 8 
        [9] => 9 
        [10] => 10 )

We can also specify the step size, for example:

$myArray = range(0, 10, 2);

This example will create an array containing 0 to 10 in steps of 2 A long array of integers, $myArray contains the following elements:

Array ( [0] => 0 
        [1] => 2 
        [2] => 4 
        [3] => 6 
        [4] => 8 
        [5] => 10 )

4. Use foreach() loop to create

We can also use foreach() loop to create a custom array, as follows Display:

$fruits = ["apple", "banana", "orange"];
$prices = [2, 3, 5];
$myArray = [];
foreach($fruits as $index => $fruit) {
    $myArray[$fruit] = $prices[$index];
}

This example will create an associative array, where the key is the name of the fruit and the key value is the price of the fruit. $myArray contains the following elements:

Array ( [apple] => 2 
        [banana] => 3 
        [orange] => 5 )

5. Use a two-dimensional array Create

We can also create a two-dimensional array. A two-dimensional array is an array containing another array.

For example:

$myArray = array(
    array("apple", 2),
    array("banana", 3),
    array("orange", 5)
);

This example creates a two-dimensional array containing three arrays. $myArray contains the following elements:

Array ( 
    [0] => Array ( [0] => apple [1] => 2 ) 
    [1] => Array ( [0] => banana [1] => 3 ) 
    [2] => Array ( [0] => orange [1] => 5 ) 
)

We can use the foreach() loop to Traverse a two-dimensional array, for example:

foreach($myArray as $value) {
    echo $value[0] . ": " . $value[1] . "<br>";
}

This code will output the following:

apple: 2
banana: 3
orange: 5

Summary:

There are many ways to customize arrays in PHP, we can Choose different methods according to specific scenarios. Using PHP's array operation functions can help us operate arrays more easily, and understanding how to use these functions can greatly improve our programming efficiency.

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