PHP Array Search Key: In this tutorial you will come to know that how to search a key of an array. array_key_exists() function helps us to search keys and returns a Boolean value. It does not work fine with multi-dimensional array, examples will illustrates these points.
PHP Array Search Key: In this tutorial you will come to know that how to search a key of an array. array_key_exists() function helps us to search keys and returns a Boolean value. It does not work fine with multi-dimensional array, examples will illustrates these points.PHP Array Search Key
To check a key of an array exists or not we use array_key_exists(). The function returns Boolean value that indicates that whether the given key exists within the array or not. If the key exists in the array it returns True or the function returns false.
General description of array_key_exists() is:
General Format | boolean array_key_exists(mixed $key, array $array) | |
Parameters | mixed $key: key to check
|
array $array: the array to be checked |
Return Value | Boolean value: True/False |
PHP Array Search Key Example 1:
<?php
$array1=array("a"=>1,"b"=>2,"c"=>3);
echo"<br/><b>Initially the values of \$array1 is:</b><br/>";
var_dump($array1);
$key="c";
echo"<br/><b>The key is:$key</b><br/>";
if(array_key_exists($key,$array1))
echo"<br/><b>Found</b><br/>";
else
echo"<br/><b>Not Found</b><br/>";
?>
Output:
Initially the values of $array1 is: array(3) { ["a"]=> int(1) ["b"]=> int(2) ["c"]=> int(3) } The key is:c Found
Example 2:
<?php
$array1=array("b"=>array("x"=>"beneath","y"=>"benign"),"c"=>"contemporary","d"=>"diligent");
echo"<br/><b>Initially the values of \$array1 is:</b><br/>";
var_dump($array1);
$key="x";
echo"<br/><b>The key is:$key</b><br/>";
if(array_key_exists($key,$array1))
echo"<br/><b>Found</b><br/>";
else
echo"<br/><b>Not Found</b><br/>";
$key="c";
echo"<br/><b>New key is:$key</b><br/>";
if(array_key_exists($key,$array1))
echo"<br/><b>Found</b><br/>";
else
echo"<br/><b>Not Found</b><br/>";
?>
Output:
Initially the values of $array1 is: array(3) { ["b"]=> array(2) { ["x"]=> string(7) "beneath" ["y"]=> string(6) "benign" } ["c"]=> string(12) "contemporary" ["d"]=> string(8) "diligent" } The key is:x Not Found New key is:c Found