What are the methods to create arrays in php

php methods to create arrays are: 1. Create using the array() function; 2. Create using the compact() function; 3. Create using the array_combine() function; 4. Create using the range() function; 5 , created using the array_fill() function.

1. Use array() to create an array

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array() creates an array, which is the most commonly used method during PHP development. To be precise, array() is a structure rather than a function.

Example 1:

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

Example 2:

$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:

$result = array();

2. Use The compact() function creates 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 variable without Strings corresponding to the name are ignored.

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

Output result:

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

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

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

Output result:

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

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

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

Definition format:

array array_combine(array1,array2)

Example

$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: When using the array_combine() function, the two parameters must have the same number 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: element step size

The following is the official definition: This function creates an array containing integers or characters from first to second (including first and 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:

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

Output result:

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

Example 2:

$number = range(0,50,10);
print_r ($number);

Output result:

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

Example 3:

$letter = range("a","d");
print_r ($letter);

Output result:

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

5. Use the array_fill() function to create an array

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

Definition format:

array_fill(start,number,value)

start: starting index

number: array number

value: array value

Example:

$a=array_fill(2,3,"Dog");
print_r($a);

Output results:

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

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