(PHP 7, PHP 8)
ReflectionFunctionAbstract::getReturnType — Gets the specified return type of a function
Gets the specified return type of a reflected function.
此函數沒(méi)有參數。
Returns a ReflectionType object if a return type is
specified, null otherwise.
示例 #1 ReflectionFunctionAbstract::getReturnType() example
<?php
function to_int($param) : int {
return (int) $param;
}
$reflection1 = new ReflectionFunction('to_int');
echo $reflection1->getReturnType();
以上例程會(huì )輸出：
int
示例 #2 Usage on built-in functions
<?php
$reflection2 = new ReflectionFunction('array_merge');
var_dump($reflection2->getReturnType());
以上例程會(huì )輸出：
null
This is because many internal functions do not have types specified for their parameters or return values. It is therefore best to avoid using this method on built-in functions.