Upgrade & Secure Your Future with DevOps, SRE, DevSecOps, MLOps!
We spend hours scrolling social media and waste money on things we forget, but won’t spend 30 minutes a day earning certifications that can change our lives.
Master in DevOps, SRE, DevSecOps & MLOps by DevOps School!
Learn from Guru Rajesh Kumar and double your salary in just one year.
We have given an array arr and a Key key, the task is to check if a key exists in an array or not in PHP.
Examples:
Input : arr = [“Devop1”, “Devop2”, “1”, “2”,”3″]
key = “2”
Output: Found the Key
Input : arr = [“Devop1”, “Devop2”, “1”, “2”,”3″]
key = 9
Output: Key not Found
The problem can be solved using PHP inbuilt function for checking key exists in a given array. The in-built function used for the given problem are:
Method 1: Using array_key_exists() Method: The array_key_exists() function checks whether a specific key or index is present inside an array or not.
Syntax:
boolean array_key_exists( $index, $array )
Example:
<?php
// PHP program to check if a key
// exists in an array or not
$array = array(
'names' => array("Devop1", "Devop2", "Devop3"),
'rank' => array('1', '2', '3')
);
// Use of array_key_exists() function
if(array_key_exists("rank", $array)) {
echo "Found the Key";
}
else{
echo "Key not Found";
}
?>Output
Found the Key
Method 2: Using isset() Method: The isset() function checks whether a specific key or index is present inside an array or not.
Syntax:
bool isset( mixed $var, mixed $… )
<?php
// PHP program to check if a key
// exists in an array or not
$array = array(
'names' => array("Devop1", "Devop2", "Devop3"),
'rank' => array('1', '2', '3')
);
// Use of array_key_exists() function
if(isset($array["rank"])){
echo "Found the Key";
}
else{
echo "Key not Found";
}
?>Output
Found the Key
