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// Get the raw data of the HyperFile and do something with it. void * rawData = nullptr ; Int rawDataSize = 0; mfs-> GetData (rawData, rawDataSize, false );

// ... do something with rawData...

This is how one can easily transfer an object (or a complete hierarchy) via network:

// By setting the write mode of the filename, it will point to a file in memory. Filename fn; AutoAlloc<MemoryFileStruct> mfs; if (mfs == nullptr ) return maxon::OutOfMemoryError( MAXON_SOURCE_LOCATION );

// No actual name needs to be set, switching mode is enough. fn. SetMemoryWriteMode (mfs); // DO NOT use fn.SetFile() or fn.SetDirectory()

// Write the object(s) into the HyperFile in memory. if ( FILEERROR::NONE != WriteHyperFile (doc, op, fn, 0)) return maxon::UnexpectedError( MAXON_SOURCE_LOCATION );

// Now, get the pointer to the HyperFile in memory and its size. void * rawData = nullptr ; Int rawDataSize = 0; // Note: Pay special attention to the last parameter, defining the ownership of the memory block. mfs-> GetData (rawData, rawDataSize, false );

// ... Send data (rawData, rawDataSize) via for example a NetworkIpConnection... SendToNetwork(rawData, rawDataSize) iferr_return ;

// This example demonstrates how to receive an object (or a hierarchy of objects) from a network connection.

// ... receive data from an NetworkIpConnection, we get a pointer to the data and the size of the data... void * rawData = nullptr ; Int rawDataSize = 0; ReceiveFromNetwork(rawData, rawDataSize); // custom helper function if (!rawData || rawDataSize == 0) return maxon::OK ; // nothing received

// By setting the read mode of the filename, it will point to a file in memory. // No actual name needs to be set, switching mode is enough. Filename fn; fn. SetMemoryReadMode (rawData, rawDataSize, false ); // DO NOT use fn.SetFile() or fn.SetDirectory()

// Read object(s) from the HyperFile in memory. AutoAlloc<BaseObject> op { Onull }; if (op == nullptr ) return maxon::OutOfMemoryError( MAXON_SOURCE_LOCATION ); String error; if ( FILEERROR::NONE != ReadHyperFile (doc, op, fn, 0, &error)) return maxon::UnknownError( MAXON_SOURCE_LOCATION );

// Insert the object(s) into the active document. doc-> InsertObject (op.Release(), nullptr , nullptr , false );

Allocation/Deallocation

MemoryFileStruct objects are created with the usual tools, see Entity Creation and Destruction Manual (Classic) .

• MemoryFileStruct::Alloc() : Allocates a memory file.
• MemoryFileStruct::Free() : Destructs memory files allocated with Alloc().

Writing Data to a File in Memory and Accessing the Raw Data

• Allocate a MemoryFileStruct .
• Set a Filename to memory write mode via Filename::SetMemoryWriteMode() .
• DO NOT set an actual filename via functions like e.g. Filename::SetFile() .
• Open the file as usual via BaseFile::Open() or HyperFile::Open() with the above Filename .
• Simply write into the file as usual.
• Close the file.
• Afterwards the raw data of the file can be accessed via MemoryFileStruct::GetData() .
• MemoryFileStruct::GetData() : Gets the data previously written to the memory file.

Reading Data From a File in Memory

• Set a Filename to memory read mode via Filename::SetMemoryReadMode() , pointing it to data in memory.
• DO NOT set an actual filename via functions like e.g. Filename::SetFile() .
• Open the file as usual via BaseFile::Open() or HyperFile::Open() with the above Filename .
• Simply read data from the file as usual.
• Close the file.

延伸阅读

• Filename Manual and especially Memory Mode
• BaseFile Manual
• HyperFile Manual