Opening Input/Output Files void openFiles ( ifstream& infile, ofstream& outfile) { char inFileName[40]; char outFileName[40]; cout<<"Enter the input file name: "; cin>>inFileName; infile.open(inFileName); //open input file cout<<"Enter the output file name: "; cin>> outFileName; outfile.open(outFileName);//open out putfile }

#ifndef n To avoid including your.h files more than once, when using multiple files (gives you a redefinition link error), add the following to all you.h files #ifndef FILE_H #define FILE_H //code goes here #endif

Three important characteristics of OOP n 1. Encapsulation - see Section 2.1 n 2. Inheritance - hierarchy in which descendant class inherits data and operations from ancestor class n Example: ottoman End table furniture chable chairtable dinette

Three important characteristics of OOP n 3. Polymorphism - several operations with same name – binding time - time name/symbol bound to code/value – static binding - resolved at compiled time – dynamic binding - resolved at run time – operation overloading - static binding

Specifying Functions n Up to now Purpose/Receives/Returns n Text Book uses Pre- and Post-conditions n Pre-condition: describes what must be true about the state for the function to work correctly n Post-condition: describes what will be true about the state if the pre-conditions are met

Specifying Functions cont. n Precondition – discusses appropriate values for receives parameters and member data of object if it is a member function we are specifying n Post-condition – describes what the return variables values will be and what changes will be made to the object

Error Conditions Describe what preconditions will be checked by the function (might use try/catch)