11.2 PHP中的面向对象（二）

在上一节里我们已经看了下如何操作一个对象的方法，这一节主要描述与对象属性有关的东西。有关如何对它进行定义的操作我们已经在上一章中描述过了，这里不再叙述，只讲对其的操作。

读取对象的属性

  1. ZEND_API zval *zend_read_property(zend_class_entry *scope, zval *object, char *name, int name_length, zend_bool silent TSRMLS_DC);
  3. ZEND_API zval *zend_read_static_property(zend_class_entry *scope, char *name, int name_length, zend_bool silent TSRMLS_DC);

zend_read_property函数用于读取对象的属性，而zend_read_static_property则用于读取静态属性。可以看出，静态属性是直接保存在类上的，与具体的对象无关。silent参数：

  • 0: 如果属性不存在，则抛出一个notice错误。
  • 1: 如果属性不存在，不报错。
如果所查的属性不存在，那么此函数将返回IS_NULL类型的zval。

更新对象的属性

  1. ZEND_API void zend_update_property(zend_class_entry *scope, zval *object, char *name, int name_length, zval *value TSRMLS_DC);
  2. ZEND_API int zend_update_static_property(zend_class_entry *scope, char *name, int name_length, zval *value TSRMLS_DC);

zend_update_property用来更新对象的属性，zend_update_static_property用来更新类的静态属性。如果对象或者类中没有相关的属性，函数将自动的添加上。

读写对象与类属性的实例

假设我们已经在扩展中定义好下面的类：

  1. class baby
  2. {
  3.     public $age;
  4.     public static $area;
  6.     public function __construct($age, $area)
  7.     {
  8.         $this->age = $age;
  9.         self::$area = $area;
  11.         var_dump($this->age, self::$area);
  12.     }
  13. }
  15. ZEND_METHOD(baby, __construct)
  16. {
  17.     zval *age, *area;
  18.     zend_class_entry *ce;
  19.     ce = Z_OBJCE_P(getThis());
  20.     if( zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "zz", &age, &area) == FAILURE )
  21.     {
  22.         printf("Error\n");
  23.         RETURN_NULL();
  24.     }
  25.     zend_update_property(ce, getThis(), "age", sizeof("age")-1, age TSRMLS_CC);
  26.     zend_update_static_property(ce, "area", sizeof("area")-1, area TSRMLS_CC);
  28.     age = NULL;
  29.     area = NULL;
  31.     age = zend_read_property(ce, getThis(), "age", sizeof("age")-1, 0 TSRMLS_DC);
  32.     php_var_dump(&age, 1 TSRMLS_CC);
  34.     area = zend_read_static_property(ce, "area", sizeof("area")-1, 0 TSRMLS_DC);
  35.     php_var_dump(&area, 1 TSRMLS_CC);
  37. }
  39. //为类添加age 和 area属性
  40. PHP_MINIT_FUNCTION(say_hello)
  41. {
  42.     zend_class_entry ce; 
  43.     INIT_CLASS_ENTRY(ce,"baby",myclass_method);
  44.     baby_ce = zend_register_internal_class(&ce TSRMLS_CC);
  46.     zend_declare_property_null(baby_ce, "age", strlen("age"), ZEND_ACC_PUBLIC TSRMLS_CC);
  47.     zend_declare_property_null(baby_ce, "area", strlen("area"), ZEND_ACC_STATIC|ZEND_ACC_PUBLIC TSRMLS_CC);
  49.     return SUCCESS;
  50. }

感谢 @看你取的破名 发现的错误。

一些其它的快捷函数

更新对象与类的属性

  1. ZEND_API void zend_update_property_null(zend_class_entry *scope, zval *object, char *name, int name_length TSRMLS_DC);
  2. ZEND_API void zend_update_property_bool(zend_class_entry *scope, zval *object, char *name, int name_length, long value TSRMLS_DC);
  3. ZEND_API void zend_update_property_long(zend_class_entry *scope, zval *object, char *name, int name_length, long value TSRMLS_DC);
  4. ZEND_API void zend_update_property_double(zend_class_entry *scope, zval *object, char *name, int name_length, double value TSRMLS_DC);
  5. ZEND_API void zend_update_property_string(zend_class_entry *scope, zval *object, char *name, int name_length, const char *value TSRMLS_DC);
  6. ZEND_API void zend_update_property_stringl(zend_class_entry *scope, zval *object, char *name, int name_length, const char *value, int value_length TSRMLS_DC);
  9. ZEND_API int zend_update_static_property_null(zend_class_entry *scope, char *name, int name_length TSRMLS_DC);
  10. ZEND_API int zend_update_static_property_bool(zend_class_entry *scope, char *name, int name_length, long value TSRMLS_DC);
  11. ZEND_API int zend_update_static_property_long(zend_class_entry *scope, char *name, int name_length, long value TSRMLS_DC);
  12. ZEND_API int zend_update_static_property_double(zend_class_entry *scope, char *name, int name_length, double value TSRMLS_DC);
  13. ZEND_API int zend_update_static_property_string(zend_class_entry *scope, char *name, int name_length, const char *value TSRMLS_DC);
  14. ZEND_API int zend_update_static_property_stringl(zend_class_entry *scope, char *name, int name_length, const char *value, int value_length TSRMLS_DC);