如果任何值为NULL,则CFPropertyListCreateDeepCopy返回nil

我使用以下CoreFoundation函数CFPropertyListCreateDeepCopy: 将不可变对象转换为可变对象.如果任何对象为NULL,则CFPropertyListCreateDeepCopy返回空.是否有任何解决方法.

self.packageArray  = CFBridgingRelease(CFPropertyListCreateDeepCopy(NULL, (CFPropertyListRef)self.packageArray , kCFPropertyListMutableContainersAndLeaves));

CFPropertyListCreateDeepCopy无法处理包含NSNull的数组/字典

示例代码

 NSArray *immutable = @[ @"a", [NSNull null], @"c" ];      
 NSMutableArray *mutable = (__bridge 
   id)CFPropertyListCreateDeepCopy(kCFAllocatorDefault, (__bridge 
        CFArrayRef)immutable, kCFPropertyListMutableContainers);

来自此链接的示例json响应

提前致谢.