An explanation of how to create a PHP array

In this article, various methods of creating arrays will be shared with you in the form of PHP example code. Friends who are interested can learn about it.

I believe that everyone has read the PHP Chinese manual before reading this article. The section on arrays was explained. How was it? How much did you understand? At least I was confused when I first read the document, maybe because the translation was not easy to understand^_^! ! Based on his own experience, UncleToo here shares various ways of creating arrays with you in the form of PHP example code. I hope it will be of some help to you (of course, you still need to read more PHP documents)

1. Use array () Create an array

array() Create an array is the most commonly used method in the PHP development process. To be precise, array() is a structure rather than a function.

Example 1:

The code is as follows:

<?php 
$number = array(1,3,5,7,9); 
$color =array("red","blue","green"); 
$student = array("name",17) 
?>

Example 2:

The code is as follows:

<?php 
$language = array(1=>"PHP",3=>"JAVA",4=>"C"); 
$student = array("name"=>"张三","age"=>17) 
?>

Of course, no value in the array is also allowed, that is, an empty array:

The code is as follows:

<?php 
$result = array(); 
?>

2. Use the compact() function to create an array

The compact() function in PHP can convert one or more variables into an array

Definition format:

array compact(var1,var2...)

Example 1 : Any string that does not have a corresponding variable name is ignored.

The code is as follows:

<?php 
$firstname = "Peter"; 
$lastname = "Griffin"; 
$age = "38"; 
$result = compact("firstname", "lastname", "age"); 
print_r($result); 
?>

Output result:

The code is as follows:

Array 
( 
[firstname] => Peter 
[lastname] => Griffin 
[age] => 38 
)

Example 2: Using a string without a corresponding variable name and an array of variable names

The code is as follows:

<?php 
$firstname = "Peter"; 
$lastname = "Griffin"; 
$age = "38"; 
$name = array("firstname", "lastname"); 
$result = compact($name, "location", "age"); 
print_r($result); 
?>

Output result:

The code is as follows :

Array 
( 
[firstname] => Peter 
[lastname] => Griffin 
[age] => 38 
)

3. Use the array_combine() function to create an array

The array_combine() function in PHP can merge two arrays into a new array, one of which is the key name , the value of the other array is the key value.

Definition format:

array array_combine(array1,array2)

Example

The code is as follows:

<?php 
$a1=array("a","b","c","d"); 
$a2=array("Cat","Dog","Horse","Cow"); 
print_r(array_combine($a1,$a2)); 
?>

Output result :

Array ([a] => Cat [b] => Dog [c] => Horse [d] => Cow )

Note: Use array_combine() function, both arguments must have the same number of elements.

4. Use the range() function to create an array

Definition format:

array range(first, second, step)

first: the minimum value of the element

second: the maximum value of the element

step: the step length of the element

The following is the official definition: This function creates an array from first to second (including first and an integer or character between second). If second is smaller than first, return the array in reverse order.

It’s difficult to understand, so let’s just look at the examples (I like to watch tutorials with examples).

Example 1:

Copy code The code is as follows:

$number = range( 0,5);
print_r ($number);
?>

Output result:

The code is as follows:

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

Example 2:

The code is as follows:

<?php 
$number = range(0,50,10); 
print_r ($number); 
?>

Output result:

The code is as follows:

Array 
( 
[0] => 0 
[1] => 10 
[2] => 20 
[3] => 30 
[4] => 40 
[5] => 50 
)

Example 3:

The code is as follows:

<?php 
$letter = range("a","d"); 
print_r ($letter); 
?>

Output result:

The code is as follows:

Array 
( 
[0] => a 
[1] => b 
[2] => c 
[3] => d 
)

5, Create an array using the array_fill() function

The array_fill() function fills the array with a given value class

Define the format:

array_fill(start,number,value)

start: Starting index

number: Number of arrays

value: Array value

Example:

The code is as follows :

<?php 
$a=array_fill(2,3,"Dog"); 
print_r($a); 
?>

Output result:

Array ( [2] => Dog [3] => Dog [4] => Dog )

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