PHP Array_key_exists An implementation method that checks whether a key name or index exists in an array _php instance

Array_key_exists ()

The PHP array_key_exists () function is used to check if the given key name or index exists in the array and returns TRUE if one exists, otherwise FALSE.

Grammar:

the bool Array_key_exists (mixed key, array search) parameter key is the given key name or index and can be any value that can be indexed as an array.

The Array_key_exists () function is also available for objects.

Example:

<?php$arr_a = array (' id ' = = 1, ' name ' = ' "admin"), if (array_key_exists (' name ', $arr _a)) {  echo ' key name exists in array $ In the Arr_a ';} else {  echo ' key name does not exist in array $arr _a ';}? >

The example output is as follows:

The key name name exists in the array $arr _a array_key_exists () function returns TRUE for array elements whose value is null. To check if the array element is NULL, use Isset ().

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