There are several formats for php arrays

With the continuous development of Web technology, PHP is becoming more and more popular among developers. PHP is a widely used scripting language that can easily expand and handle various complex businesses. In PHP, arrays are an indispensable data type, and almost all programs use arrays. So, what types do PHP arrays have? Let’s take a look at it together.

1. Numeric array

Numeric array is the most common array type in PHP. It is an array with numbers as array subscripts. Each numeric subscript in a numeric array corresponds to a specific element. For example, the following code defines an array named $arr that contains three elements.

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

In this example, $arr is a numeric array containing three string elements.

2. Associative array

Associative array is another common PHP array type. This type of array uses strings as subscripts. Specifically, each string subscript in the associative array corresponds to a specific element. For example, the following code defines an array named $age, using people's names as string subscripts.

$age = array("Peter"=>"35", "Ben"=>"37", "Joe"=>"43");

In this example, $age is an associative array that contains three elements, each element represents a person's name and age.

3. Multidimensional array

Multidimensional array refers to an array that contains other arrays. In PHP we can easily create multi-dimensional arrays. For example, the following code defines an array named $marks, which contains two arrays with indexes 0 and 1.

$marks = array(
    array("Physics", 80, 75),
    array("Math", 90, 88),
);

In this example, $marks is an array containing two arrays. Each small array has three elements, representing the scores in physics, mathematics and Chinese respectively.

4. Array comparison

In addition to conventional array types, PHP also provides many methods to compare array types. The most common comparison methods are the array_diff() and array_intersect() functions.

array_diff() function can be used to compare the difference between two arrays. For example:

$array1 = array("a", "b", "c");
$array2 = array("c", "d", "e");

$result = array_diff($array1, $array2);

In this example, the $result array will contain different elements from the original array, namely "a" and "b".

Instead, the array_intersect() function can be used to find duplicate elements between two arrays. For example:

$array1 = array("a", "b", "c");
$array2 = array("c", "d", "e");

$result = array_intersect($array1, $array2);

In this example, the $result array will contain duplicate elements, which is "c".

Summary

In PHP, arrays are an indispensable data type, and almost all programs use arrays. Common array types include numeric arrays, associative arrays, and multidimensional arrays. PHP provides many methods to compare array types. The most common comparison methods are the array_diff() and array_intersect() functions. When you need to handle various complex businesses, PHP arrays provide you with many convenient functions, which are worthy of deep mastery by developers.

The above is the detailed content of There are several formats for php arrays. For more information, please follow other related articles on the PHP Chinese website!