php all keys in array

1<?php
2$array = array(
3    'fruit1' => 'apple',
4    'fruit2' => 'orange',
5    'fruit3' => 'grape',
6    'fruit4' => 'apple',
7    'fruit5' => 'apple');
8
9$keys = array_keys($array);		// return array
10$values = array_values($array);	// return array
11?>

1$array = array(0 => 100, "cor" => "vermelho");
2print_r(array_keys($array));
3
4$array = array("azul", "vermelho", "verde", "azul", "azul");
5print_r(array_keys($array, "azul"));
6
7$array = array("cor"     => array("azul", "vermelho", "verde"),
8               "tamanho" => array("pequeno", "medio", "grande"));
9print_r(array_keys($array));
10

1<?php
2$age=array("Peter"=>"35","Ben"=>"37","Joe"=>"43");
3foreach($age as $x=>$x_value)
4  {
5  echo "Key=" . $x . ", Value=" . $x_value;
6  echo "<br>";
7  }
8?>

1
2<?php
3$array = array(
4    'fruit1' => 'apple',
5    'fruit2' => 'orange',
6    'fruit3' => 'grape',
7    'fruit4' => 'apple',
8    'fruit5' => 'apple');
9
10// this cycle echoes all associative array
11// key where value equals "apple"
12while ($fruit_name = current($array)) {
13    if ($fruit_name == 'apple') {
14        echo key($array).'<br />';
15    }
16    next($array);
17}
18?>
19
20