PHP uksort() Function

PHP uksort() Function

The uksort() function in PHP sorts an array by keys using a user-defined comparison function.

Syntax

uksort ( array &$array , callable $key_compare_func )

Parameter

array(required)- This parameter represents the input array.

key_compare_func(required)- This parameter represents a string that describe a callable comparison function. The comparison function must return an integer <, =, or > than 0 if the first argument is <, =, or > than the second argument.

Return

This function returns a Boolean value TRUE on success or FALSE on failure.

Example 1

"Reema",2=>"Varun",1=>"Joe",4=>"Ron",3=>"Jai");
 //original array
 echo("Original array: \n");
 print_r($array);
 //sorting the array by keys using "strcasecmp" comparison function
 uksort($array,"strcasecmp");
 //printing the sorted array
 echo("\nSorted array: \n"); 
 print_r($array);
 ?> 

Output

Original array: 
 Array
 (
     [5] => Reema
     [2] => Varun
     [1] => Joe
     [4] => Ron
     [3] => Jai
 ) 
 Sorted array: 
 Array
 (
     [1] => Joe
     [2] => Varun
     [3] => Jai
     [4] => Ron
     [5] => Reema
 ) 

Example 2

$b)? 1: 0;  
 } 
 // initializing the Input Array
 $array1 = array(15=>"Reema", 10=>"raj", 30=>"Atul"); 
 echo("Original Array: \n");
 print_r($array1);
 // Sorting an array by keys using "my_function" comparison function
 uksort ($array1,"my_function");
 echo("\nSorted Array: \n"); 
 print_r($array1);
 ?> 

Output

Original Array: 
 Array
 (
     [15] => Reema
     [10] => raj
     [30] => Atul
 )
 Sorted Array:  
 Array
 (
     [10] => raj
     [15] => Reema
     [30] => Atul
 ) 

Example 3

"Reema", "Age"=>23,"Country"=>"India");
 //original array
 echo("Original array: \n");
 print_r($array);
 //sorting the array with keys
 uksort($array,"strcasecmp" );
 //printing the sorted array
 echo("\nSorted array: \n");
 print_r($array);
 ?> 

Output

Original array: 
 Array
 (
     [Name] => Reema
     [Age] => 23
     [Country] => India
 )
 Sorted array without second parameter: 
 Array 
 (
     [Age] => 23
     [Country] => India
     [Name] => Reema
 )