C大学教程第五版课后习题答案第39章

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GradeBook类定义：

#include // program uses C++ standard string class using std::string; class GradeBook { public:

// constructor initializes course name and instructor name GradeBook( string, string );

void setCourseName( string ); // function to set the course name string getCourseName(); // function to retrieve the course name void setInstructorName( string ); // function to set instructor name string getInstructorName(); // function to retrieve instructor name void displayMessage(); // display welcome message and instructor name private:

string courseName; // course name for this GradeBook string instructorName; // instructor name for this GradeBook }; // end class GradeBook 类成员函数：

#include using std::cout; using std::endl; #include GradeBook.h

// constructor initializes courseName and instructorName // with strings supplied as arguments

GradeBook::GradeBook( string course, string instructor ) {

setCourseName( course ); // initializes courseName

setInstructorName( instructor ); // initialiZes instructorName } // end GradeBook constructor // function to set the course name

void GradeBook::setCourseName( string name ) {

courseName = name; // store the course name } // end function setCourseName

// function to retrieve the course name string GradeBook::getCourseName() { return courseName;

} // end function getCourseName // function to set the instructor name

void GradeBook::setInstructorName( string name ) { instructorName = name; // store the instructor name

} // end function setInstructorName

// function to retrieve the instructor name string GradeBook::getInstructorName() { return instructorName;

} // end function getInstructorName

// display a welcome message and the instructor's name void GradeBook::displayMessage() {

// display a welcome message containing the course name cout << Welcome to the grade book for\\n << getCourseName() << ! << endl;

// display the instructor's name cout << This course is presented by: << getInstructorName() << endl; } // end function displayMessage 测试文件：

#include using std::cout; using std::endl;

// include definition of class GradeBook from GradeBook.h #include GradeBook.h

// function main begins program execution int main() {

// create a GradeBook object; pass a course name and instructor name GradeBook gradeBook(

CS101 Introduction to C++ Programming, Professor Smith ); // display initial value of instructorName of GradeBook object cout << gradeBook instructor name is:

<< gradeBook.getInstructorName() << \\n\\n; // modify the instructorName using set function

gradeBook.setInstructorName( Assistant Professor Bates ); // display new value of instructorName

cout << new gradeBook instructor name is:

<< gradeBook.getInstructorName() << \\n\\n; // display welcome message and instructor's name