11/29/2022 0 Comments Camcamx serial macheha![]() ![]() For usage information and an example, see the GetObjectSchema member function of class CArchive. If you want your Serialize member function to be able to read multiple versions - that is, files written with different versions of the application - you can use the value VERSIONABLE_SCHEMA as an argument to the IMPLEMENT_SERIAL macro. If the schema number of the object on disk does not match the schema number of the class in memory, the library will throw a CArchiveException, preventing your program from reading an incorrect version of the object. (Don't confuse this schema number with database terminology.) The MFC serialization code checks the schema number when reading objects into memory. Use an integer greater than or equal to 0 for the schema number. The schema number is essentially a version number for objects of the class. ![]() (CamCamX, Eltima Virtual Serial Ports Driver XP comes in handy when you don't have enough serial. The third argument to this macro is a schema number.įree sitecom camera driver downloads. The first two arguments to the macro are the name of the class and the name of its immediate base class. You use this macro in the implementation file (.CPP) for your class. The IMPLEMENT_SERIAL macro is used to define the various functions needed when you derive a serializable class from CObject. Note If you forget to define a constructor with no arguments in a class that uses the DECLARE_SERIAL and IMPLEMENT_SERIAL macros, you will get a 'no default constructor available' compiler warning on the line where the IMPLEMENT_SERIAL macro is used. The constructor must put the object in a state that allows it to be deleted if necessary. If you make it protected or private, you help make sure that it will only be used by the serialization functions. This constructor can be declared public, protected, or private. The deserialization process will fill in all member variables with the values required to re-create the object. MFC requires a default constructor when it re-creates your objects as they are deserialized (loaded from disk). The following class declaration fragment shows the new member variables and the declaration for the overridden Serialize member function. Using the results of IsStoring as a guide, you either insert your object's data in the CArchive object with the insertion operator ( >).Ĭonsider a class that is derived from CObject and has two new member variables, of types CString and WORD. The object has a member function, IsStoring, which indicates whether Serialize is storing (writing data) or loading (reading data). The Serialize function has a CArchive argument that it uses to read and write the object data. The Serialize member function, which is defined in the CObject class, is responsible for actually serializing the data necessary to capture an object's current state. ![]()
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