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Streams and Classes

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I''ve been reading your book "Teach Yourself C++ in 21 Days 3rd ED.", it is a great book! But still I have a problem Ok, I''m trying to create a class that could save itself, that is, save all it''s member datas to a file. Unfortunately I''m having problems...Have a look, if you dare: class COORDIM { private: int coorX, coorY; int dimWidth, dimHeight; public: //accessors int GetX() const { return (coorX); }//end inclince int GetY() const { return (coorY); }//end incline int GetWidth() const { return (dimWidth); }//end inclince int GetHeight() const { return (dimHeight); }//end incline void SetX(int x) { coorX = x; }//end incline void SetY(int y) { coorY = y; }//end incline void SetWidth(int width) { dimWidth = width; }//end incline void SetHeight(int height) { dimHeight = height; }//end incline }; class TILEMAP { private: LPCTSTR MapFile; //The filename to be saved or loaded COORDIM MapInfo; //Contains the coordinates and dimension public: //Constructors TILEMAP(LPCTSTR FileName); //Constructor, initial filename ~TILEMAP(); //Deconstructor //public accessors LPCTSTR GetMapFile() const //Used to get the filename { return MapFile; }//end incline void SetMapFile(LPCTSTR FileName) //Set MapFile { MapFile = FileName; }//end incline COORDIM GetMapInfo() const { return (MapInfo); }//end incline void SetMapInfoX(int x) { MapInfo.SetX(x); } void SetMapInfoY(int y) { MapInfo.SetY(y); } void SetMapInfoWidth(int width) { MapInfo.SetWidth(width); } void SetMapInfoHeight(int height) {MapInfo.SetHeight(height); } int SaveMap(); //Need to include fstream.h to use int LoadMap(); //Needs fstream.h }; ///Constructor TILEMAP::TILEMAP(LPCTSTR Filename): MapFile(Filename) //Initialize MapFile { }///End Constructor ///Deconstructor TILEMAP::~TILEMAP() { }///End Deconstructor /////LoadMap TILEMAP::SaveMap() { ofstream CurrentFile(MapFile, ios::binary);//Open file for binary if (!CurrentFile) { cout << "Error opening file " << MapFile << "for writing.\n"; return (0); }//end if CurrentFile.write((char *)&MapInfo, sizeof(MapInfo)); //success return (1); } Ok, the fourth line from the bottom... CurrentFile.write((char *)&MapInfo, sizeof(MapInfo)); doesn''t make any sense to me although I came up with it. Basically I want to write the data stored to MapInfo to the file. How do I know which block of memory on the file it is writen to in case I have more than one class data that I want to save and later load? Or is there a better way to save informations to a file? For example, if you''re making a game which has a Level.lev file and that should contains data of the classes LevelName, LevelCharaters, etc...Is there a way to write/read certain bits of memory from a file in whole classes?

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