PHP/Data Structure/array walk

Apply a user function to every member of an array.

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<? $fruits = array ("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); function test_alter (&$item1, $key, $prefix) {

   $item1 = "$prefix: $item1";

} function test_print ($item2, $key) {

   echo "$key. $item2
\n";

} array_walk ($fruits, "test_print"); reset ($fruits); array_walk ($fruits, "test_alter", "fruit"); reset ($fruits); array_walk ($fruits, "test_print"); ?>

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Applying Functions to Array Elements Using array_walk()

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<?php

 function array_display($array, $pre=FALSE)
 {
   $tag = $pre ? "pre" : "p";
   printf("<%s>%s</%s>\n", $tag, var_export($array, TRUE), $tag);
 }
 function modify(&$element)
 {
   $element *= 1.5;
 }
 $array = array(10, -3.5, 2, 7);
 array_display($array, TRUE);
 array_walk($array, "modify");
 array_display($array, TRUE);

?>

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array_walk() function applies a function to several or all elements in an array.

   <source lang="html4strict">

Its syntax is: int array_walk(array array, string func_name, [mixed data])

<? //Using array_walk() to delete duplicates in an array:

   function delete_dupes($element) {
        static $last="";
        if ($element == $last)
             unset($element);
        else
             $last=$element;
   }
   
   $emails = array("b@b.ru", "c@w.ru", "b@b.ru");
   
   sort($emails);
   print_r($emails);
   echo "
";
   reset($emails);
   print_r($emails);
   echo "
";
   array_walk($emails,"delete_dupes");
   print_r($emails);
   echo "
";
   

?>

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