php check if array subscript exists

PHP method to check whether array subscript exists

array_key_exists() function

array_key_exists () function determines whether the specified key exists in an array. If the key exists, it returns true, otherwise it returns false.

Syntax:

array_key_exists(key,array)

Parameter description:

key required. Specifies the key name.

array Required. Specifies the input array.

Instance:

"Dog","b"=>"Cat"); if (array_key_exists("a",$a)) { echo "Key exists!"; } else { echo "Key does not exist!"; } ?>

Output:

Key exists!

Instance:

"Dog","b"=>"Cat"); if (array_key_exists("c",$a)) { echo "Key exists!"; } else { echo "Key does not exist!"; } ?>

Output:

Key does not exist!

Instance:

Output:

Key exists!

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