How to trim all strings in an array in PHP ?

Given a string array with white spaces, the task is to remove all white spaces from every object of an array.
Examples:

Input: arr = ["Geeks  ", "   for", "  Geeks  "]
Output:
Geeks
for
Geeks

Method 1: Using trim() and array_walk() function:

• trim() Function: The trim() function is an inbuilt function which removes whitespaces and also the predefined characters from both sides of a string that is left and right.
  Syntax:
  

trim( $string, $charlist )

• array_walk() Function: The array_walk() function is an inbuilt function in PHP which walks through the entire array regardless of pointer position and applies a callback function or user-defined function to every element of the array. The array element’s keys and values are parameters in the callback function.
  Syntax:
  

boolean array_walk( $array, myFunction, $extraParam )

Example:

php

<?php

// Create an array with whitespace
$arr = array( "Geeks  ", "  for", "   Geeks   ");

// Print original array
echo "Original Array:\n";
foreach($arr as $key => $value)
    print($arr[$key] . "\n");

// Iterate array through array_walk() function
// and use trim() function to remove all
// whitespaces from every array objects
array_walk($arr, create_function('&$val',
                    '$val = trim($val);'));

// Print modify array
echo "\nModified Array:\n";
foreach($arr as $key => $value)
    print($arr[$key] . "\n");

?>

Output:

Original Array:
Geeks  
  for
   Geeks   

Modified Array:
Geeks
for
Geeks

Method 2: Using trim() and array_map() function:

• The array_map() function is an inbuilt function in PHP which helps to modify all elements one or more arrays according to some user-defined condition in an easy manner. It basically, sends each of the elements of an array to a user-defined function and returns an array with new values as modified by that function.
  Syntax:
  

array_map(functionName, arr1, arr2...)

Example:

php

<?php

// Create an array with whitespace
$arr = array( "Geeks  ", "  for", "   Geeks   ");

// Print original array
echo "Original Array:\n";
foreach($arr as $key => $value)
    print($arr[$key] . "\n");

// Iterate array through array_map() function
// Using trim() function to remove all
// whitespaces from every array objects
$arr = array_map('trim', $arr);

// Print modify array
echo "\nModified Array:\n";
foreach($arr as $key => $value)
    print($arr[$key] . "\n");

?>

Output:

Original Array:
Geeks  
  for
   Geeks   

Modified Array:
Geeks
for
Geeks

Method 3: Basic method using for loop: Use for loop to traverse each element of array and then use trim() function to remove all white space from array elements.
Example:

php

<?php

// Create an array with whitespace
$arr = array( "Geeks  ", "  for", "   Geeks   ");

// Print original array
echo "Original Array:\n";
foreach($arr as $key => $value)
    print($arr[$key] . "\n");

// Print modify array
echo "\nModified Array:\n";

// Iterate array through for loop
// Using trim() function to remove all
// whitespaces from every array objects
foreach($arr as $key => $value) {
    $arr[$key] = trim($value);

    // Print current object of array
    print($arr[$key] . "\n");
}

?>

Output:

Original Array:
Geeks  
  for
   Geeks   

Modified Array:
Geeks
for
Geeks