How to return the value of a single column in an input array in PHP

php editor Banana will introduce you how to return the value of a single column in the input array. In PHP, you can use the array_column() function to achieve this functionality. The array_column() function can return the value of the specified key from a multi-dimensional array and form an array of these values. By specifying the array and key name, you can quickly obtain the value of the required column. This function can help you quickly filter and process arrays and improve programming efficiency.

Return the value of a single column in the input array in PHP

In php, there are many ways to extract the value of a specific column from an array. The following are some commonly used methods:

Use array_column() function

array_column() The function is specially designed to extract the value of a specific column from a multi-dimensional array. It returns a new array where each element corresponds to the value of the specified column in the input array. The syntax is as follows:

array_column($array, $column_key)

in:

• $array: The array from which to extract columns.
• $column_key: The key name of the column to be extracted.

Example:

$input_array = [
["name" => "John", "age" => 30],
["name" => "Mary", "age" => 25],
["name" => "Bob", "age" => 35],
];

$ages = array_column($input_array, "age");

// $ages will contain the following values:
// [30, 25, 35]

Using loops and indexes

If you don't want to use the array_column() function, you can use a loop and index to manually extract the column value. This is less efficient for large arrays, but feasible for small arrays.

Example:

$input_array = [
["name" => "John", "age" => 30],
["name" => "Mary", "age" => 25],
["name" => "Bob", "age" => 35],
];

$ages = [];
foreach ($input_array as $row) {
$ages[] = $row["age"];
}

// $ages will contain the following values:
// [30, 25, 35]

Use map() function

Another way is to use the map() function, which maps one array to another array. You can use anonymous functions to extract the desired value from each element.

Example:

$input_array = [
["name" => "John", "age" => 30],
["name" => "Mary", "age" => 25],
["name" => "Bob", "age" => 35],
];

$ages = array_map(function ($row) {
return $row["age"];
}, $input_array);

// $ages will contain the following values:
// [30, 25, 35]

Choose the best method

Which method to choose depends on your array size and specific requirements. For small arrays or situations where you need to extract values ​​from multiple columns, the array_column() function is the best choice. For large arrays, looping and indexing methods are less efficient, and the map() function is a good choice.

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