C 课件：第三章.ppt

第三章 类和对象  从下面三个例子中，注意结构如何转换到类的发展过程 一、结构 (1)一个简单的结构:Time struct Time{ int hour; int minute; int second; }; 一个例子： int main(int argc, char* argv[]){ char c; struct Time{ int hour; int minute; int second; }; //结构的定义 Time timeObject,timeArray[10],*timePtr,*timePtr1,timeRef=timeObject; ? //结构的引用 timeObject.hour=3; timeObject.minute=10; timeObject.second=55; cout时间1为：timeObject.hour: timeObject.minute:timeObject. secondendl; timeArray[6]=timeObject; timeArray[6].hour=23; cout时间2为：timeArray[6].hour: timeArray[6].minute: timeArray[6].secondendl; timePtr=timeObject; (*timePtr).hour=13; cout时间3为：(*timePtr).hour :(*timePtr).minute:(*timePtr). secondendl; cout时间3为：timePtr-hour: timePtr-minute:timePtr-second endl; timeRef.hour=15; cout时间4为：timeRef.hour:timeRef.minute: timeRef.second endl; cout时间4为：timeObject.hour:timeObject.minute: timeObject. secondendl; cout时间4为：(*timePtr).hour:“ (*timePtr).minute:(*timePtr). secondendl; } (2)、一个带有处理方法的结构:Time 例子二： ? struct Time { // structure definition int hour; // 0-23 int minute; // 0-59 int second; // 0-59 }; void printMilitary( const Time ); // function prototype void printStandard( const Time ); // prototype int main(){ Time dinnerTime; //variable of new type Time ? //set members to valid values dinnerTime.hour = 18; dinnerTime.minute = 30; dinnerTime.second = 0; ? cout Dinner will be held at ; printMilitary( dinnerTime ); //注意：对象作为参数；函数不附属于对象 cout military time,\nwhich is ; printStandard( dinnerTime ); //张三用可以自己的方法取李四的银子 cout standard time.\n; ? // set members to invalid values dinnerTime.hour = 29; dinnerTime.minute = 73; ? cout \nTime with invalid values: ; printMilitary( dinnerTime ); cout endl; ? return 0; } void printMili