to pass in a unknown data and retrieving it

[themadme]

i want to set a class back to its original structure after calling a receive function. code below to explain

class Node
{
	public:
	Node(){}
	~Node(){}
};


class lol  : public Node
{
	public:
	string strName;
};

class face
{
	public:

	void vSetLOL( CONST Node &C_lol )
	{
		this->C_lol  = C_lol;
	}

	const Node getLoL( void ) const
	{
		return C_lol;
	}

	priavte:

	Node C_lol ;	
}


main
{
	lol  C_lol;
	face C_face;

	C_lol.strname = "gums";

	C_face.vSetLOL( C_lol );

	C_lol.strname = " monkey";


	////// how do you change the node C_lol back to lol C_lol /////
	C_lol = C_face.getLOL();  /// this is the main problem

}

[Ganon11]

You may be able to cast C_face.getLOL() to a C_lol, or have the face class hold a lol object instead of a Node object.

[Banfa]

The bottom line is that you can't. As soon as you copied a class lol to a class Node the value of any data members held in the lol were lost forever.

You may be able to write a constructor and operator= for lol that will take a Node & as the parameter but you will never be able to reconstruct any data held in lol.

[themadme]

Thanks for the replies and sorry about the bad naming in the last example

would that be the same problem if put a structure into a buffer.

//// class called Data
Data::Data()
{
    char *pcPacket = new char;
}

void Data::setPacketData( const char* pcPacketData )
{
    *pcPacket = *pcPacketData;
}

void Data::getPacketData( const char* pcPacketData )
{
    *pcPacketData = *pcPacket;
}

int main
{
     stucture vector3
     {
          int x,y, z;
     };

     Data C_Data;
     vector3 vec3;

      /// this would work
     C_Data.setPacketData( (char*)&vec3 );    

      /// this would not work, the returned data would not change?
      C_Data.getPacketData( (char*)&vec3 );    
    
     return 0;
}

so the returned data would be impossible to change or is there a mystic way? if was integers or floats that was put into the buffer, i know that would work but not with structures

when i allocate the pcPacket, i should put it into an array, depending on the size of the structure that was sent right?

[themadme]

oops found the problem, such amateur mistake, im only coping over one byte of data. someone slap me

[arnaudk]

*SLAP*!
Oops, message too short... *SLAP* *SLAP* *SLAP* ;-)

[themadme]

lol ok, new prob, will actually it not a problem yet.

I would just some comments back to see what i'm doing is correct.

//////////// this would be done on both sides of the server and the client
#define BUFFERSIZE 80

struct PacketData
{
	float x,y,z;

}S_PacketData;

struct Data
{
	char *pcPacket;
	char *cpName;
}S_Data;

S_Data.pcPacket = new char[ sizeof(PacketData) ];
S_Data.cpName = NULL;

char *NetPacket = new char[ sizeof(PacketData) + BUFFERSIZE ];

//////////////////////////////////////////////////////////////////////////////////////

//////// then on the client side it would do this to send information ////////////////

S_PacketData.x = 5.0f;
S_PacketData.y = 15.0f;
S_PacketData.z = 25.0f;

S_Data.cpName = "lols";

memcpy( S_Data.pcPacket, &S_PacketData, sizeof(PacketData) );

memcpy( NetPacket, &S_Data, sizeof(PacketData) + BUFFERSIZE );

send(s, NetPacket, sizeof(PacketData) + BUFFERSIZE,0);


///////////// on the server would have this ///////////////////

recv (s, NetPacket, sizeof(PacketData) + BUFFERSIZE,0);

/////// is this correct so far? /////////////////////////////////