78-对象属性读写

78-对象属性读写

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

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

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，用具体的对象无关。

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：

ZEND_API void zend_update_property(zend_class_entry *scope, zval *object, char *name, int name_length, zval *value TSRMLS_DC);
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：

class baby
{
    public $age;
    public static $area;

    public function __construct($age, $area)
    {
        $this->age = $age;
        self::$area = $area;

        var_dump($this->age, self::$area);
    }
}

ZEND_METHOD(baby, __construct)
{
    zval *age, *area;
    zend_class_entry *ce;
    ce = Z_OBJCE_P(getThis());
    if( zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "zz", &age, &area) == FAILURE )
    {
        printf("Error\n");
        RETURN_NULL();
    }
    zend_update_property(ce, getThis(), "age", sizeof("age")-1, age TSRMLS_CC);
    zend_update_static_property(ce, "area", sizeof("area")-1, area TSRMLS_CC);

    age = NULL;
    area = NULL;

    age = zend_read_property(ce, getThis(), "age", sizeof("age")-1, 0 TSRMLS_DC);
    php_var_dump(&age, 1 TSRMLS_CC);

    area = zend_read_static_property(ce, "area", sizeof("area")-1, 0 TSRMLS_DC);
    php_var_dump(&area, 1 TSRMLS_CC);

}

一些其它的快捷函数

ZEND_API void zend_update_property_null(zend_class_entry *scope, zval *object, char *name, int name_length TSRMLS_DC);
ZEND_API void zend_update_property_bool(zend_class_entry *scope, zval *object, char *name, int name_length, long value TSRMLS_DC);
ZEND_API void zend_update_property_long(zend_class_entry *scope, zval *object, char *name, int name_length, long value TSRMLS_DC);
ZEND_API void zend_update_property_double(zend_class_entry *scope, zval *object, char *name, int name_length, double value TSRMLS_DC);
ZEND_API void zend_update_property_string(zend_class_entry *scope, zval *object, char *name, int name_length, const char *value TSRMLS_DC);
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);


ZEND_API int zend_update_static_property_null(zend_class_entry *scope, char *name, int name_length TSRMLS_DC);
ZEND_API int zend_update_static_property_bool(zend_class_entry *scope, char *name, int name_length, long value TSRMLS_DC);
ZEND_API int zend_update_static_property_long(zend_class_entry *scope, char *name, int name_length, long value TSRMLS_DC);
ZEND_API int zend_update_static_property_double(zend_class_entry *scope, char *name, int name_length, double value TSRMLS_DC);
ZEND_API int zend_update_static_property_string(zend_class_entry *scope, char *name, int name_length, const char *value TSRMLS_DC);
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);