TMS 119
New Member
I'm a little rusty with C++ so bear with me.
My assignment has me amending a database file by adding 'tombstones' to records that are to be omitted later by the destructor. The database brings in a file (lets call it A) then there is a menu of operations. If the user wants to remove a file, they use the remove option which places a 'b' (in this case) in front of the Social Security Number.
That is all fine and good. My amendments take care of that. NOW, I'm having problems writing the new database that excludes the tombstoned records. I can get it to print to the screen, but I can't get it to print out. I know I need to define an fstream object, and use it in a function called writeToFile(). But it doesn't work.
database is declared as a type fstream
Here is my destructor:
//function to omit tombstoned items, write data to file
template<class T>
Database<T>::~D atabase()
{
T tmp; //variable to access student file
fstream newDatabase; //my attempt at declaring the new database object
database.open(f Name,ios::in|io s::binary); //this works fine
while (true )
{
tmp.readFromFil e(database);
if database.eof()) //finish when at the end of file
break;
if(!tmp.isNull( )) //check for tombstone
{
//newDatabase = database; //doesn't work
//tmp.writeToFile (newDatabase); //this causes
//infinite loop
cout << tmp << endl; // omits tombstoned items //prints to screen just fine
}
}
database.close( );
}
any suggestions?
1 1955
have you received any replies? It seems that there are some pieces missing within your destructor. Post the whole code and i'll check it out.
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