ios如何将model转换成NSDictionary

- (NSDictionary *)properties_aps {

NSMutableDictionary *props = [NSMutableDictionary dictionary];

unsigned int outCount, i;

objc_property_t *properties = class_copyPropertyList([self class], &outCount);

for (i = 0; i < outCount; i++) {

objc_property_t property = properties[i];

const char* char_f =property_getName(property);

NSString *propertyName = [NSString stringWithUTF8String:char_f];

id propertyValue = [self valueForKey:(NSString *)propertyName];

if (propertyValue) [props setObject:propertyValue forKey:propertyName];

}

free(properties);

return props;

}