PHP数组分割与数组接合

$fruits = array("Apple", "Banana", "Orange", "Pear", "Grape", "Lemon", "Watermelon");
$subset = array_slice($fruits, 3);
print_r($subset);
// output
// Array ( [0] => Pear [1] => Grape [2] => Lemon [3] => Watermelon )
?>

然后，使用下负长度：

$fruits = array("Apple", "Banana", "Orange", "Pear", "Grape", "Lemon", "Watermelon");
$subset = array_slice($fruits, 2, -2);
print_r($subset);
// output
// Array ( [0] => Orange [1] => Pear [2] => Grape )
?>

接合数组 array_splice()

array_splice()函数会删除数组中从offset开始到offset+length 结束的所有元素，并以数组的形式返回所删除的元素。其形式为： array array_splice ( array array , int offset[,length[,array replacement]]) offset 为正值时，则接合将从距数组开头的offset 位置开始，offset 为负值时，接合将从距数组末尾的offset 位置开始。如果忽略可选的length 参数，则从offset 位置开始到数组结束之间的所有元素都将被删除。如果给出了length 且为正值，则接合将在距数组开头的offset + leng th 位置结束。相反，如果给出了length且为负值，则结合将在距数组开头的count(input_array)-length的位置结束。

例子：

$fruits = array("Apple", "Banana", "Orange", "Pear", "Grape", "Lemon", "Watermelon");
$subset = array_splice($fruits, 4);
print_r($fruits);
print_r($subset);
// output
// Array ( [0] => Apple [1] => Banana [2] => Orange [3] => Pear )
// Array ( [0] => Grape [1] => Lemon [2] => Watermelon )
?>

可以使用可选参数replacement来指定取代目标部分的数组。

例子：

$fruits = array("Apple", "Banana", "Orange", "Pear", "Grape", "Lemon", "Watermelon");
$subset = array_splice($fruits, 2, -1, array("Green Apple", "Red Apple"));
print_r($fruits);
print_r($subset);
// output
// Array ( [0] => Apple [1] => Banana [2] => Green Apple [3] => Red Apple [4] => Watermelon )
// Array ( [0] => Orange [1] => Pear [2] => Grape [3] => Lemon )
?>