PHP5添加了一項(xiàng)新的功能:Reflection。這個功能使得程序員可以reverse-engineer class, interface,function,method and extension。通過PHP代碼,就可以得到某object的所有信息,并且可以和它交互。
假設(shè)有一個類Person:
03 | * For the sake of demonstration, we"re setting this private |
05 | private $_allowDynamicAttributes = false; |
07 | /** type=primary_autoincrement */ |
10 | /** type=varchar length=255 null */ |
16 | public function getId() |
20 | public function setId( $v ) |
24 | public function getName() |
28 | public function setName( $v ) |
32 | public function getBiography() |
34 | return $this ->biography; |
36 | public function setBiography( $v ) |
38 | $this ->biography = $v ; |
通過ReflectionClass,我們可以得到Person類的以下信息:
- 常量 Contants
- 屬性 Property Names
- 方法 Method Names
- 靜態(tài)屬性 Static Properties
- 命名空間 Namespace
- Person類是否為final或者abstract
只要把類名"Person"傳遞給ReflectionClass就可以了:
1 | $class = new ReflectionClass( 'Person' ); |
獲取屬性(Properties):
1 | $properties = $class ->getProperties(); |
2 | foreach ( $properties as $property ) { |
3 | echo $property ->getName(). "\n" ; |
6 | // _allowDynamicAttributes |
默認(rèn)情況下,ReflectionClass會獲取到所有的屬性,private 和 protected的也可以。如果只想獲取到private屬性,就要額外傳個參數(shù):
1 | $private_properties = $class ->getProperties(ReflectionProperty::IS_PRIVATE); |
可用參數(shù)列表:
- ReflectionProperty::IS_STATIC
- ReflectionProperty::IS_PUBLIC
- ReflectionProperty::IS_PROTECTED
- ReflectionProperty::IS_PRIVATE
如果要同時獲取public 和private 屬性,就這樣寫:ReflectionProperty::IS_PUBLIC | ReflectionProperty::IS_PROTECTED
應(yīng)該不會感覺陌生吧。
通過$property->getName()可以得到屬性名,通過getDocComment可以得到寫給property的注釋。
01 | foreach ( $properties as $property ) { |
02 | if ( $property ->isProtected()) { |
03 | $docblock = $property ->getDocComment(); |
04 | preg_match( '/ type\=([a-z_]*) /' , $property ->getDocComment(), $matches ); |
05 | echo $matches [1]. "\n" ; |
09 | // primary_autoincrement |
有點(diǎn)不可思議了吧。竟然連注釋都可以取到。
獲取方法(methods):通過getMethods() 來獲取到類的所有methods。返回的是ReflectionMethod對象的數(shù)組。不再演示。
最后通過ReflectionMethod來調(diào)用類里面的method。
01 | $data = array ( "id" => 1, "name" => "Chris" , "biography" => "I am am a PHP developer" ); |
02 | foreach ( $data as $key => $value ) { |
03 | if (! $class ->hasProperty( $key )) { |
04 | throw new Exception( $key . " is not a valid property" ); |
07 | if (! $class ->hasMethod( "get" .ucfirst( $key ))) { |
08 | throw new Exception( $key . " is missing a getter" ); |
11 | if (! $class ->hasMethod( "set" .ucfirst( $key ))) { |
12 | throw new Exception( $key . " is missing a setter" ); |
15 | // Make a new object to interact with |
16 | $object = new Person(); |
18 | // Get the getter method and invoke it with the value in our data array |
19 | $setter = $class ->getMethod( "set" .ucfirst( $key )); |
20 | $ok = $setter ->invoke( $object , $value ); |
22 | // Get the setter method and invoke it |
23 | $setter = $class ->getMethod( "get" .ucfirst( $key )); |
24 | $objValue = $setter ->invoke( $object ); |
27 | if ( $value == $objValue ) { |
28 | echo "Getter or Setter has modified the data.\n" ; |
30 | echo "Getter and Setter does not modify the data.\n" ; |
有點(diǎn)意思吧。
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