希望大家昨天与家人度过了愉快的时光!在出城探望家人时，我想我应该开始一些截止日期即将到来的项目，其中之一是将用 C 编写的代码转换为 C++，该代码使用结构数组来存储和修改数据使用对象数组的代码。虽然我最近熟悉了 C 编程语法，但这将是我的第一个 C++ 项目。我知道类应该与结构非常相似，但我对语法以及访问说明符的概念感到困惑。下面是我的原始 C 代码，以及要进行的更改的列表。任何有关如何开始的建议，包括此类工作的良好资源/教程，将不胜感激。预先感谢您的考虑!
修改:
- 将类中的所有数据声明为私有(private)；
- 提供提供所有必需功能的方法(类函数) 让你的程序正常工作。特别是，声明一个构造函数方法 类(class)。
- 除了程序所需的方法外，还编写一个访问(\get")和 类中每个私有(private)数据成员的 mutator (\set") 函数。
我的代码:
#include <stdio.h>
#include <conio.h>
#include <string.h>
#include <stdlib.h>
//Function Prototypes
void insertFirstName(struct structureName[], char[], int);
void insertLastName(struct structureName[], char[], int);
void insertHomeNumber(struct structureName[], char[], int);
void insertCellNumber(struct structureName[], char[], int);
void printPhoneBook(struct structureName[], int);
int deleteFriend(struct structureName[], char[], int);
void showFriend(struct structureName[], char[], int);
void saveFile(FILE*, struct structureName[], int);
int loadFile(FILE*, struct structureName[]);
//Structure Declaration
typedef struct structureName{
char *fName; //member for First Name
char *lName; //member for Last Name
char *hPhone; //member for Home Phone
char *cPhone; //member for Cell Phone
} pbFriend;
int main(){
int x = 0;
int flag = 0; //returned in delete function to account for empty phonebook
int entryCount = 0;//variable for count of entries
int menuChoice = 0; //variable for switch statement
int count = 0; //counter keeps track of entry numbers
char name[100] = {'\0'}; //place holder for entries
pbFriend phoneBook[1000] = {'\0'}; //create instance
char fileSave = '\0'; //variable for selection on file save query
char fileLoad = '\0'; //variable for selection on file load query
FILE *pbData; //file pointer
do{
//load file to phone book query
printf("Welcome! Would you like to load a file into the phonebook? (y/n): ");
scanf("%c",&fileLoad);
getchar();
if(fileLoad=='y'||fileLoad=='Y'){
count = loadFile(pbData,phoneBook);
printf("Success! File loaded!\n");
entryCount = count;
} //end if
else{
if(fileLoad!='n'&&fileLoad!='N'){
printf("Invalid selection.\n");
} //end if
} //end else
}while( fileLoad!='y'&&fileLoad!='Y'&&fileLoad!='n'&&fileLoad!='N'); //end do while
do{
//display menu
printf("\nPhone Book Application\n");
printf("1) Add friend\n");
printf("2) Delete friend\n");
printf("3) Show a friend\n");
printf("4) Show phone book\n");
printf("5) Quit\n");
printf("What do you want to do?: ");
scanf("%d",&menuChoice);
getchar();
switch(menuChoice){
case 1: //add friend case
printf("\nFirst name: "); //insert first name
scanf("%s",name);
getchar();
//allocate memory
phoneBook[count].fName = (char*)malloc(100*sizeof(char));
//memory failed to allocate
if(phoneBook[count].fName == NULL){
printf("ERROR! Out of memory!");
}//end if
//memory allocated
else{
insertFirstName(phoneBook, name, count);
}//end else
printf("Last name: "); //insert last name
scanf("%s",name);
getchar();
//allocate memory
phoneBook[count].lName = (char*)malloc(100*sizeof(char));
//memory failed to allocate
if(phoneBook[count].lName == NULL){
printf("ERROR! Out of memory!");
}//end if
//memory allocated
else{
insertLastName(phoneBook, name, count);
}//end else
printf("Phone number (home): "); //insert home number
scanf("%s",name);
getchar();
//allocate memory
phoneBook[count].hPhone = (char*)malloc(100*sizeof(char));
//memory failed to allocate
if(phoneBook[count].hPhone == NULL){
printf("ERROR! Out of memory!");
}//end if
//memory allocated
else{
insertHomeNumber(phoneBook, name, count);
}//end else
printf("Phone number (cell): "); //insert cell number
scanf("%s",name);
getchar();
//allocate memory
phoneBook[count].cPhone = (char*)malloc(100*sizeof(char));
//memory failed to allocate
if(phoneBook[count].cPhone == NULL){
printf("ERROR! Out of memory!");
}//end if
//memory allocated
else{
insertCellNumber(phoneBook, name, count);
}//end else
printf("Entry added to phone book!\n");
printf("\n");
count++;
entryCount++;
break;
case 2: //delete friend case
printf("\nPlease provide a last name for entry deletion: ");
scanf("%s",&name);
getchar();
strcat(name," "); //white space for string values
flag = deleteFriend(phoneBook, name, count);
//successful deletion
if(flag == 1){
printf("The entry has been deleted from the phonebook.\n");
entryCount--;
}//end if
//no deletion
else{
printf("No deletion has been made.\n");
}
printf("\n");
break;
case 3: //show friend case
printf("\n");
printf("Please provide a last name: ");
scanf("%s",&name);
getchar();
strcat(name," ");
showFriend(phoneBook, name, count);
printf("\n");
break;
case 4: //show phone book case
printf("\n");
//empty phonebook
if(entryCount == 0){
printf("The phonebook is empty.\n");
}//end if
else{
printPhoneBook(phoneBook, count);
}//end else
printf("\n");
break;
case 5: //quit case
do{
printf("\nWould you like to save the phonebook to a file? (y/n): ");
scanf("%c",&fileSave);
getchar();
switch(fileSave){
case 'y': case 'Y': //save case
saveFile(pbData,phoneBook,count);
printf("Success! File saved!");
break;
case 'n': case 'N': //exit without saving case
printf("Good bye!\n");
break;
default: //invalid case
printf("Invalid selection.\n");
break;
} //end switch
}while(fileSave!='y'&&fileSave!='Y'&&fileSave!='n'&&fileSave!='N'); //end do while
break;
default: //invalid case
printf("Invalid menu choice.\n\n");
break;
}//end switch statement
}while(menuChoice != 5); //end do while loop
getch();
return 0;
}//end main
//Function Definitions
//function to insert first name
void insertFirstName(pbFriend phoneBook[], char name[], int count){
strcpy(phoneBook[count].fName, name);
strcat(phoneBook[count].fName," ");
}
//function to insert last name
void insertLastName(pbFriend phoneBook[], char name[], int count){
strcpy(phoneBook[count].lName, name);
strcat(phoneBook[count].lName," ");
}
//function to insert home phone number
void insertHomeNumber(pbFriend phoneBook[], char name[], int count){
strcpy(phoneBook[count].hPhone, name);
strcat(phoneBook[count].hPhone," ");
}
//function to insert cell phone number
void insertCellNumber(pbFriend phoneBook[], char name[], int count){
strcpy(phoneBook[count].cPhone, name);
strcat(phoneBook[count].cPhone," ");
}
//function to delete entry
int deleteFriend(pbFriend phoneBook[], char name[], int count){
int x;
int foundFlag = 0; //foundFlag for seeing if query is in structure
char nullStr[30] = {'\0'}; //NULL string
char name2[30] = {'\0'}; //string to store first name query
//get first name to prevent multiple deletions due to same last name
printf("Please provide the first name of the entry to be deleted: ");
scanf("%s", &name2);
getchar();
strcat(name2," ");
for(x=0;x<count;x++){
if((strcmp(phoneBook[x].lName,name)==0)&&(strcmp(phoneBook[x].fName,name2)==0)){
foundFlag = 1; //entry found, proceed with delete
//free previously allocated memory
free(phoneBook[x].fName);
free(phoneBook[x].lName);
free(phoneBook[x].hPhone);
free(phoneBook[x].cPhone);
//set free strings to NULL
strcpy((phoneBook[x].fName), nullStr);
strcpy((phoneBook[x].lName), nullStr);
strcpy((phoneBook[x].hPhone), nullStr);
strcpy((phoneBook[x].cPhone), nullStr);
}//end if
}//end for
//entry not found
if(foundFlag == 0){
printf("\nSorry, there is nobody with that name in the phone book.\n");
}//end if
return foundFlag;
}//end function
//function to search entries by last name
void showFriend(pbFriend phoneBook[], char name[], int count){
int x;
int foundFlag = 0; //foundFlag for seeing if query is in structure
printf("\n");
for(x=0;x<count;x++){
if(strcmp((phoneBook[x].lName), name) == 0){
foundFlag = 1; //entry found, proceed with display
printf("%s",phoneBook[x].fName);
printf("%s",phoneBook[x].lName);
printf("%s(home) ",phoneBook[x].hPhone);
printf("%s(cell)",phoneBook[x].cPhone);
printf("\n");
}//end if
}//end for
//entry not found
if(foundFlag == 0){
printf("Sorry, there is nobody with that name in the phone book.\n");
}//end if
}//end function
//function to print phone book contents
void printPhoneBook(pbFriend phoneBook[], int count){
int x;
for(x=0;x<count;x++){
//check to avoid NULL strings, which have been deleted
if(strlen(phoneBook[x].fName) > 0){
printf("%s", phoneBook[x].fName);
printf("%s", phoneBook[x].lName);
printf("%s(home) ", phoneBook[x].hPhone);
printf("%s(cell)", phoneBook[x].cPhone);
printf("\n");
}//end if
}//end for
}//end function
//function to save to a file
void saveFile(FILE *pbData, pbFriend phoneBook[], int count){
char fileName[100] = {'\0'}; //string to store desired name to save file as
int x = 0; //counter variable
printf("Please enter the file name: ");
scanf("%s",fileName);
getchar();
//open file
pbData = fopen(fileName,"w");
//file open fail case
if(pbData == NULL){
printf("ERROR! File not saved!\n");
perror("The following error occurred"); //specifies i/o error
getchar();
exit(EXIT_FAILURE); //exit program with error
} //end if
//file open success case
else{
//write to file
for(x=0;x<count;x++){
fprintf(pbData, "%s", phoneBook[x].fName);
fprintf(pbData, "%s", phoneBook[x].lName);
fprintf(pbData, "%s", phoneBook[x].hPhone);
fprintf(pbData, "%s", phoneBook[x].cPhone);
} //end for
fclose(pbData);
} //end else
}// end function
//function to load a file into the phone book
int loadFile(FILE *pbData, pbFriend phoneBook[]){
char fileName[100] = {'\0'}; //variable to store name of file to load
int count = 0; //counter variable
char tabulaRasa[30] = {'\0'}; /*NULL string to clear garbage data from the
last loop of the feof() condition when loading
files*/
printf("Please enter the name of the file you wish to load: ");
scanf("%s",fileName);
getchar();
//open file
pbData = fopen(fileName,"r");
//file open fail case
if(pbData == NULL){
printf("ERROR! Unable to load file!\n");
perror("The following error occurred"); //specifies i/o error
getchar();
exit(EXIT_FAILURE); //exit program with error
} //end nested if
//file open success case
else{
//allocate memory to store data from a file
while(!feof(pbData)){
phoneBook[count].fName = (char*)malloc(100*sizeof(char));
if(phoneBook[count].fName == NULL){
printf("ERROR! Out of memory!");
} //end double nested if
phoneBook[count].lName = (char*)malloc(100*sizeof(char));
if(phoneBook[count].lName == NULL){
printf("ERROR! Out of memory!");
} //end double nested if
phoneBook[count].hPhone = (char*)malloc(100*sizeof(char));
if(phoneBook[count].hPhone == NULL){
printf("ERROR! Out of memory!");
} //end double nested if
phoneBook[count].cPhone = (char*)malloc(100*sizeof(char));
if(phoneBook[count].cPhone == NULL){
printf("ERROR! Out of memory!");
} //end double nested if
//load from file
fscanf(pbData,"%s",phoneBook[count].fName);
strcat(phoneBook[count].fName," ");
fscanf(pbData,"%s",phoneBook[count].lName);
strcat(phoneBook[count].lName," ");
fscanf(pbData,"%s",phoneBook[count].hPhone);
strcat(phoneBook[count].hPhone," ");
fscanf(pbData,"%s",phoneBook[count].cPhone);
strcat(phoneBook[count].cPhone," ");
count++; //show that entry/entries have been made from file
}//end while loop
//free memory of last entry (junk data from feof() condition)
free(phoneBook[count-1].fName);
free(phoneBook[count-1].lName);
free(phoneBook[count-1].hPhone);
free(phoneBook[count-1].cPhone);
//set newly free strings to NULL
strcpy((phoneBook[count-1].fName), tabulaRasa);
strcpy((phoneBook[count-1].lName), tabulaRasa);
strcpy((phoneBook[count-1].hPhone), tabulaRasa);
strcpy((phoneBook[count-1].cPhone), tabulaRasa);
count--;
} //end nested else
fclose(pbData);
return(count); //show that phone book is not empty
} //end if
最佳答案
开始手头任务的一个绝妙方法是查看 C++ Getting Started 中的一些项目。页。
关于c++ - 将 C 结构转换为 C++ 类，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/13535302/