(PHP 5)
ReflectionClass::getConstructor — 获取类的构造函数
此函数没有参数。
一个 ReflectionMethod 对象，反射了类的构造函数。
Example #1 ReflectionClass::getConstructor() 的基本用法
<?php
$class = new ReflectionClass('ReflectionClass');
$constructor = $class->getConstructor();
var_dump($constructor);
?>
以上例程会输出：
object(ReflectionMethod)#2 (2) {
["name"]=>
string(11) "__construct"
["class"]=>
string(15) "ReflectionClass"
}
jochem at drecomm dot nl (2011-05-13 08:13:02)
Old constructors also count as contructor:
<?php
class SomeClass {
function SomeClass($some_arg) {
}
}
$refl = new ReflectionClass('SomeClass');
var_dump($refl->isInstantiable()); // bool(true)
echo $refl->getConstructor();
/* OUTPUT:
Method [ <user, ctor> public method SomeClass ] {
@@ /var/www/vhosts/api.example.com/httpdocs/testRefl.php 5 - 6
- Parameters [1] {
Parameter #0 [ <required> $some_arg ]
}
}
*/
?>
Some more behavior:
<?php
class SomeClass {
function funcA($arg1, $arg2) {
}
}
$refl = new ReflectionClass('SomeClass');
var_dump($refl->isInstantiable()); // bool(true)
var_dump($refl->getConstructor()); // NULL
/* --------------- */
class AnotherClass {
private function __construct() {
}
function funcB($arg1, $arg2) {
}
}
$refl = new ReflectionClass('AnotherClass');
var_dump($refl->isInstantiable()); // bool(false)
echo $refl->getConstructor();
/*
Method [ <user, ctor> private method __construct ] {
@@ /testRefl.php 22 - 23
}
*/
?>
Tested on PHP 5.2.4
Rob McVey (2010-07-16 07:47:34)
Just posting some example code for anyone wanting to mess around with this stuff:
<?php
class Say
{
private $what_to_say;
public function __construct($no_default, $word = "Hello World", $options = array('a', 'b'))
{
$this->what_to_say = $word;
}
public function speak()
{
echo $this->what_to_say;
}
}
$class = new ReflectionClass('Say');
$constructor = $class->getConstructor();
echo $constructor;
/* OUTPUTS:
Method [ <user, ctor> public method __construct ] {
@@ /reflect.php 6 - 9
- Parameters [3] {
Parameter #0 [ <required> $no_default ]
Parameter #1 [ <optional> $word = 'Hello World' ]
Parameter #2 [ <optional> $options = Array ]
}
}
*/
$parameters = $constructor->getParameters();
var_export($parameters);
/* OUTPUT:
array (
0 =>
ReflectionParameter::__set_state(array(
'name' => 'no_default',
)),
1 =>
ReflectionParameter::__set_state(array(
'name' => 'word',
)),
2 =>
ReflectionParameter::__set_state(array(
'name' => 'options',
)),
)
*/
$nl = "\n";
echo "$nl\tParameters$nl";
foreach($parameters as $param)
{
echo "****** $" . $param->name . " ******$nl";
echo "Nullable:\t\t" . $param->allowsNull() . $nl
."Default Value:\t\t";
echo ($param->isDefaultValueAvailable()) ? $param->getDefaultValue() : "None";
echo $nl ."Is Array:\t\t";
echo ($param->isArray()) ? "Yes" : "No";
echo $nl . "Optional:\t\t";
echo ($param->isOptional()) ? "Yes" : "No";
echo $nl;
}
/* OUTPUT:
Parameters
****** $no_default ******
Nullable: 1
Default Value: None
Is Array: No
Optional: No
****** $word ******
Nullable: 1
Default Value: Hello World
Is Array: No
Optional: Yes
****** $options ******
Nullable: 1
Default Value: Array
Is Array: No
Optional: Yes
*/
?>
To clarify the possibly confusing behavior of ReflectionParemeter::isArray(), it will return true if the parameter has type hinting:
<?php
...
public function __construct($no_default, $word = "Hello World", array $options = array('a', 'b'))
...
?>
Calling isArray() will now return true for the $options parameter