ReflectionFunctionAbstract::getReturnType
(PHP 7)
ReflectionFunctionAbstract::getReturnType — Gets the specified return type of a function
说明
Gets the specified return type of a reflected function.
参数
此函数没有参数。
返回值
Returns a ReflectionType object if a return type is specified, NULL otherwise.
范例
Example #1 ReflectionFunctionAbstract::getReturnType() example
<?php
function to_int($param) : int {
return (int) $param;
}
$reflection1 = new ReflectionFunction('to_int');
echo $reflection1->getReturnType();
以上例程会输出：
int
Example #2 Usage on built-in functions
<?php
$reflection2 = new ReflectionFunction('array_merge');
var_dump($reflection2->getReturnType());
以上例程会输出：
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.
参见
- ReflectionFunctionAbstract::hasReturnType() - Checks if the function has a specified return type
- ReflectionType::__toString() - To string
