ReflectionFunctionAbstract::getReturnType()
版本:php7
(PHP 7)
Gets the specified return type of a function
说明
public ReflectionFunctionAbstract::getReturnType(void) :ReflectionType
Gets the specified return type of a reflected function.
参数
此函数没有参数。
返回值
Returns aReflectionTypeobject if a return type is specified,NULL
otherwise.
范例
Example #1ReflectionFunctionAbstract::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
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