How to Sort an Array by Keys in PHP?

Problem:

You have an array which has some elements in it. You want to search the array by its keys.

Solution:

There are few ways you can sort an array by its keys-

Method 1: Using ksort() function

ksort() function sorts an array by keys in ascending order. See the following example-

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<pre> <?php $age = array(         "Peter" => 34,         "John" => 27,         "Smoth" => 30,         "Jack" => 32         );               if(ksort($age))     print_r($age); ?> </pre>

Output:

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Array(         [Jack] => 32         [John] => 27         [Peter] => 34         [Smoth] => 30 )

Line 9-10

After successful sorting the $age[] array by keys, ksort() function returns true, otherwise returns false. If it sorts successfully, we print the sorted array in line 10.

Method 2: Using krsort() function

krsort() function sorts an array by keys in reverse order. See the following example-

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<pre> <?php $age = array(         "Peter" => 34,         "John" => 27,         "Smoth" => 30,         "Jack" => 32         );   if(krsort($age))  print_r($age); ?> </pre>

Output:

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Array(           [Smoth] => 30           [Peter] => 34           [John] => 27           [Jack] => 32 )

Line 10-11

After successful sorting the array $age[] by keys, krsort() function returns true, otherwise false. If it sorts successfully, we print the sorted array in line 11.