ReflectionFunctionAbstract::getReturnType

(PHP 7)

ReflectionFunctionAbstract::getReturnType — Gets the specified return type of a function

说明

public ReflectionType ReflectionFunctionAbstract::getReturnType ( void )

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()