New functions for arrays in PHP8 make array operations easier
With the continuous development of the PHP language, many new functions have been added to the PHP8 version, among which the new functions for arrays make it even easier Array operations are easier.
The following will introduce the new functions for arrays in the PHP8 version, including:
- array_is_list() function
This function is used to check whether an array It is an ordinary index array, that is, the key values of the array are consecutive numbers such as 0, 1, 2, 3, etc.
For example, in the PHP8 version, you can use this function like this:
$array1 = [1, 2, 3]; $array2 = [1, "key" => "value", 3]; var_dump(array_is_list($array1)); // 输出bool(true) var_dump(array_is_list($array2)); // 输出bool(false)
- array_contains() function
This function is used to check whether an array contains A certain value exists.
For example, this function can be used in the PHP8 version:
$array = [1, 2, 3]; var_dump(array_contains($array, 2)); // 输出bool(true) var_dump(array_contains($array, 4)); // 输出bool(false)
- array_key_first() and array_key_last() functions
These two functions are respectively Used to get the first and last key name of the array.
For example, you can use these two functions like this in the PHP8 version:
$array = ["key1" => "value1", "key2" => "value2", "key3" => "value3"]; var_dump(array_key_first($array)); // 输出string(4) "key1" var_dump(array_key_last($array)); // 输出string(4) "key3"
- $index parameter in the array_map() function
In PHP8 In this version, a new $index parameter is added to the array_map() function, which is used to pass the index of the current array element.
For example, in the PHP8 version, you can use this parameter like this:
$array = ["apple", "banana", "orange"]; $newArray = array_map(function($value, $index) { return $index . " : " . $value; }, $array, array_keys($array)); print_r($newArray);
In the above code, we get the $array array by passing the array_keys($array) array as the second parameter. key name to get the index of the array element.
- array_is_associative() function
This function is used to check whether an array is an associative array, that is, the key value of the array is the key name of the string.
For example, you can use this function like this in the PHP8 version:
$array1 = ["key1" => "value1", "key2" => "value2"]; $array2 = [1, 2, 3]; var_dump(array_is_associative($array1)); // 输出bool(true) var_dump(array_is_associative($array2)); // 输出bool(false)
Summary
Through the above introduction, we can see that some new functions have been added in the PHP8 version. New functions for arrays. These functions not only allow us to operate arrays more conveniently, but also improve the readability and simplicity of the code. During the development process, we can make full use of these functions to improve our coding efficiency.
The above is the detailed content of New functions for arrays in PHP8 make array operations easier. For more information, please follow other related articles on the PHP Chinese website!

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