Instance Method

decodeTopLevelObjectOfClass:forKey:error:

Decode an object as an expected type, failing if the archived type does not match.

Declaration

- (id)decodeTopLevelObjectOfClass:(Class)aClass forKey:(NSString *)key error:(NSError * _Nullable *)error;

Parameters

aClass

The expected class of the object being decoded.

key

The archive key indicating the member to decode.

error

On return, an NSError indicating why decoding failed, or nil if no error occurred.

Return Value

The decoded object, or nil if decoding fails.

Discussion

If the coder responds YES to requiresSecureCoding, then the coder calls failWithError: in either the following cases:

  • The class indicated by cls does not implement NSSecureCoding.

  • The unarchived class does not match cls, nor do any of its superclasses.

If the coder does not require secure coding, it ignores the cls parameter and does not check the decoded object.

See Also

Decoding Top-Level Objects

- decodeTopLevelObjectOfClasses:forKey:error:

Decode an object as one of several expected types, failing if the archived type does not match.

- decodeTopLevelObjectAndReturnError:

Decodes a previously-encoded object, populating an error if decoding fails.

- decodeTopLevelObjectForKey:error:

Decodes the previously-encoded object associated by a key, populating an error if decoding fails.