Ds\Map::isEmpty

(PECL ds >= 1.0.0)

Ds\Map::isEmpty — Returns whether the map is empty

说明

public Ds\Map::isEmpty ( void ) : bool

Returns whether the map is empty.

参数

此函数没有参数。

返回值

Returns TRUE if the map is empty, FALSE otherwise.

范例

Example #1 Ds\Map::isEmpty() example

<?php
$a = new \Ds\Map(["a" => 1, "b" => 2, "c" => 3]);
$b = new \Ds\Map();

var_dump($a->isEmpty());
var_dump($b->isEmpty());
?>

以上例程的输出类似于：

bool(false)
bool(true)
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