PHP 数组转字符串，与字符串转数组

代码示例：
1，implode 将数组变成字符串

$array = array('lastname', 'email', 'phone');

$comma_separated = implode(",", $array);

echo $comma_separated; // lastname,email,phone


// Empty string when using an empty array:
var_dump(implode('hello', array())); // string(0) ""



 
 2，explode — 分割字符串，返回一个数组

// 示例 1
$pizza  = "piece1 piece2 piece3 piece4 piece5 piece6";

$pieces = explode(" ", $pizza);

echo $pieces[0]; // piece1

echo $pieces[1]; // piece2
 

// 示例 2
$data = "foo:*:1023:1000::/home/foo:/bin/sh";

list($user, $pass, $uid, $gid, $gecos, $home, $shell) = explode(":", $data);

echo $user; // foo

echo $pass; // *


3，str_split — 将字符串转换为数组
$str = "Hello Friend";
 
$arr1 = str_split($str);/*将字符串逐个拆分*/
$arr2 = str_split($str, 3);/*三个一组拆分*/
 
print_r($arr1);
print_r($arr2);
 
输出结果
Array
(
    [0] => H
    [1] => e
    [2] => l
    [3] => l
    [4] => o
    [5] =>
    [6] => F
    [7] => r
    [8] => i
    [9] => e
    [10] => n
    [11] => d
)
 
Array
(
    [0] => Hel
    [1] => lo
    [2] => Fri
    [3] => end
)