Methods to iterate through an array

pradeep's Avatar author of Methods to iterate through an array
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This is an article on Methods to iterate through an array in PHP.
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I was wondering in how many ways can we iterate through an array in PHP. So, I figured out a few, here's it...

Our Array, which we will be iterating on,
PHP Code:
$arr = array('PHP','Perl', 'JavaScript','AJAX', 'Python','ASP', 'C#'); 
1. Using a simple for loop
PHP Code:
// using for loop
 for($i=0;$i<count($arr);$i++)
 {
     print("$arr[$i]\n");
 } 
2. Using foreach
PHP Code:
// using foreach
 foreach($arr as $val)
 {
     print("$val\n");
 } 
3. Using a while loop
Code: PHP
// using while loop
 $i=0;
 while($val=$arr[$i++])
 {
     print("$val\n");
 }
4. Using the array_walk function
PHP Code:
// using array_walk function
 function print_item($item,$key)
 {
     print("$item\n");
 }
 
 array_walk($arr,'print_item'); 
5. Using an user function
PHP Code:
// using a function, and recursively calling it
 function print_recurse(&$a)
 {
     printf("%s\n",array_pop($a));
     print_recurse($a);
 }
 
 print_recurse($arr) 
Team Leader
10May2007,00:08   #2
pradeep's Avatar
Sorry for the bug which I overlooked, the function will run into infinite recursion, so the correct one should look like this.

PHP Code:
 // using a function, and recursively calling it
function print_recurse(&$a)
{
    printf("%s\n",array_pop($a));
    // check whether array has any elements, or else it'll become an infinite recursion
    if(count($a)>0)
        print_recurse($a);
}

print_recurse($arr);