Ds\Map::__ construct()function是PHP中的内置函数, 用于创建新实例。
语法如下：
public Ds\Map::__construct( $values )参数：该函数接受单个参数$值包含可遍历的对象或数组以使用初始值。
下面的程序说明了Ds\Map::__ construct()PHP中的功能：
程序1：
<?php
//PHP program to illustrate the __construct()
//function of Ds\map
//Declare a new Map
$map = new \Ds\Map();
//Display the map elements
print_r( $map );
//Creating a Map
$map = new \Ds\Map([
"1" => "Geeks" , "2" => "for" , "3" => "Geeks"
]);
//Display the map elements
print_r( $map );
?>输出如下：
Ds\Map Object
(
)
Ds\Map Object
(
[0] => Ds\Pair Object
(
[key] => 1
[value] => Geeks
)
[1] => Ds\Pair Object
(
[key] => 2
[value] => for
)
[2] => Ds\Pair Object
(
[key] => 3
[value] => Geeks
)
)程序2：
<?php
//PHP program to illustrate the __construct()
//function of Ds\map
//Creating a Map
$map = new \Ds\Map([ "1" => "10" , "2" => "20" , "3" => 30]);
//Display key-value pair
print_r( $map );
//Creating another Map
$map = new \Ds\Map([1 => "Welcome" , 2 => "to" , 3 => "lsbin" ]);
//Display key-value pair
print_r( $map );
?>输出如下：
Ds\Map Object
(
[0] => Ds\Pair Object
(
[key] => 1
[value] => 10
)
[1] => Ds\Pair Object
(
[key] => 2
[value] => 20
)
[2] => Ds\Pair Object
(
[key] => 3
[value] => 30
)
)
Ds\Map Object
(
[0] => Ds\Pair Object
(
[key] => 1
[value] => Welcome
)
[1] => Ds\Pair Object
(
[key] => 2
[value] => to
)
[2] => Ds\Pair Object
(
[key] => 3
[value] => lsbin
)
)参考： https://www.php.net/manual/en/ds-map.construct.php
