Preface: bloggers have written two interesting small projects before: tic-tac-toe and mine clearance Next, the blogger continues to update a small project - address book, including three versions, static version, dynamic version and file saving version. Next, let's explain how to implement the static version.
catalogue
1, Overview of static address book
2, Implementation of static address book interface function
1. Basic structure of static address book
2. Game framework (for users to choose)
6. Judge whether the address book is empty
8. Delete the specified contact
9. Find the designated contact
10. Modify the designated contact
1, Overview of static address book
Static address book: fixed length array is used, that is, the length of the array cannot be changed. We can set the number of members that can be recorded in the address book to 1000.
2, Implementation of static address book interface function
| file name | function |
| Contact.c | Implementation of address book function interface |
| Contact.h | Macro definition, header file, declaration of interface function |
| test.c | Function interface test |
1. Basic structure of static address book
An address book is a structure.
Contains: 1. Address book member array. Each address book member is a structure, including address, name, age, gender, address and telephone.
2. Variable indicating the number of address book members.
Note: in order to change the size of the address book in order, it is recommended to use the macro definition
//Note that the macro definition should not be followed by a semicolon!!!! Otherwise there will be problems
#define NAME_MAX 30 // Maximum length of name
#define SEX_MAX 5 // Gender maximum length
#define TELE_MAX 12 // Maximum telephone length
#define ADDR_MAX 30 // Maximum address length
#define MAX 1000 // The total number of members in the address book array
typedef struct PeoInfo
{
char name[NAME_MAX];
int age;
char sex[SEX_MAX];
char addr[ADDR_MAX];
char tele[TELE_MAX];
}PeoInfo;
struct Contact //mail list
{
PeoInfo data[MAX]; //Structure member array
int size; //Indicates the number of members contained in the address book and controls the subscript of the array
};2. Game framework (for users to choose)
enum Option
{
EXIT,
ADD,
DEL,
SEARCH,
MODIFY,
SHOW,
DESTORY,
};
void menu()
{
printf("******************************\n");
printf("**** 1. add 2. del *****\n");
printf("**** 3. search 4. modify****\n");
printf("**** 5. show 6. Destory ***\n");
printf("**** 0. exit **\n");
printf("******************************\n");
}
int main()
{
int input = 0;
struct Contact con; //Create an address book containing MAX structure members
InitContact(&con); //Initialize address book
do
{
menu();
printf("Please select->\n");
scanf("%d", &input);
switch (input)
{
case ADD:
ADDContact(&con);
break;
case DEL:
DelContact(&con);
break;
case SEARCH:
SearchContact(&con);
break;
case MODIFY:
ModifyContact(&con);
break;
case SHOW :
ShowContact(&con);
break;
case DESTORY:
DesContact(&con);
break;
case EXIT:
printf("Exit succeeded! Welcome to use again!\n");
break;
default:
printf("Selection error,Please reselect\n");
break;
}
} while (input);
return 0;
}3. Initialize address book
Initializing the address book member array with memset
Writing 1: size of each member * number of members
void InitContact(struct Contact* ps)
{
assert(ps);
//There was no data at first
memset(ps->data, 0, sizeof(PeoInfo) * MAX); //The address book member array is initialized to 0
ps->size = 0;//The default member is 0
}Writing method 2: the array is placed separately in sizeof - > the size of the whole array is calculated
//Writing method 2
void InitContact(struct Contact* ps)
{
memset(ps->data, 0, sizeof(ps->data));
//PS - > data gets the array name of the PenInfo array in the address book
//The array list is placed inside sizeof, and the size of the entire array is calculated
ps->size = 0;
}4. Print address book
In order to be more intuitive, we can also print the title. By traversing the address book member array, the members can be printed.
//This is a right alignment. If you want to align left - > -% 30d, add a sign in front of% and a minus sign in front of% numbers
void ShowContact(struct Contact* ps)
{
int i = 0;
//Print title
printf("%15s\t%5s\t%8s\t%15s\t%30s\t\n\n", "name", "age", "sex", "tele", "addr");
//Prints the contents of each structure member in the array
for (i = 0; i < ps->size; i++)
{
printf("%15s\t%5d\t%8s\t%15s\t%30s\n",
ps->data[i].name,
ps->data[i].age,
ps->data[i].sex,
ps->data[i].tele,
ps->data[i].addr);
}
}5. Increase in membership
Writing method 1: directly operate on the address book member array
void ADDContact(struct Contact* ps)
{
//First determine whether the address book is full
if (ps->size == MAX)
{
printf("The address book is full\n");
}
else
{
printf("Please enter your first name:");
scanf("%s", ps->data[ps->size].name); //Array name is not used&
printf("Please enter age: ");
scanf("%d", &(ps->data[ps->size].age));
printf("Please enter the address:");
scanf("%s", ps->data[ps->size].addr);
printf("Please enter the number:");
scanf("%s", ps->data[ps->size].tele);
printf("Please enter gender:");
scanf("%s", ps->data[ps->size].sex);
printf("Added successfully\n");
ps->size++; //Added a member, size++
}
}Writing method 2: first create a temporary structure member, and then assign it to the PS - > size position in the address book structure array after assignment
//Add member 2:
void ADDContact(struct Contact* ps)
{
PeoInfo tmp = { 0 };
//First determine whether the address book is full
if (ps->size == MAX)
{
printf("The address book is full\n");
}
else
{
printf("Please enter your first name:");
scanf("%s", tmp.name); //Array name is not used&
printf("Please enter age: ");
scanf("%d", &(tmp.age));
printf("Please enter the address:");
scanf("%s", tmp.addr);
printf("Please enter the number:");
scanf("%s", tmp.tele);
printf("Please enter gender:");
scanf("%s", tmp.sex);
ps->data[ps->size] = tmp;
printf("Added successfully\n");
ps->size++;
}
}6. Judge whether the address book is empty
Because the size flag indicates the number of members in the address book, you can know whether the address book is empty by judging whether the size is 0
//If it is empty, the judgment is true and 1 is returned
bool EmptyContact(struct Contact* ps)
{
return ps->size == 0;
}7. Find function
Because the subsequent deletion of the specified contact and the change of the information of the specified contact need to be searched, the search function can be encapsulated separately
If found, return the corresponding subscript. If not found, return - 1
Because it is not modified, you can add const modification
Method: traverse the structure member array to find
int FindContactByName(const struct Contact* ps,const char*name )
{
//Traversal search
int i = 0;
for(i = 0;i< ps->size;i++)
{
if( strcmp(name,ps->data[i].name) == 0)
{
//Return subscript
return i;
}
}
return -1;
}8. Delete the specified contact
Note: delete contact - > start from this location, and the subsequent data will be overwritten
If the address book is empty, it will not be deleted and will be returned directly
void DelContact(struct Contact* ps)
{
if (EmptyContact(ps))
{
printf("The address book is empty and cannot be deleted\n");
return ;
}
char name[NAME_MAX] = { 0 }; //Used to store the name of the specified contact to be deleted
printf("Please enter the name of the person to delete:>");
scanf("%s",name);
//lookup
int pos = FindContactByName(ps, name);
if (pos == -1)
{
printf("The specified contact does not exist\n");
}
else
{
//Delete operation
//Start at the pos position and cover the rear forward
int i = 0;
for (i = pos; i < ps->size - 1; i++)
{
ps->data[i] = ps->data[i + 1];
}
//Deleted element, size--
ps->size--;
printf("Delete succeeded\n");
}
}9. Find the designated contact
Method: enter the name of the contact to be searched, call the search function to search, if found, return the corresponding subscript, and print the corresponding information of the contact corresponding to the subscript
void SearchContact(const struct Contact* ps)
{
char name[NAME_MAX] = {0};
printf("Enter the contact you want to find:>");
scanf("%s",name);
int pos =FindContactByName(ps,name);
if(pos == -1)
{
printf("The contact you are looking for does not exist\n");
}
else
{
// Print the information corresponding to the contact
//Print title
printf("%15s\t%5s\t%8s\t%15s\t%30s\t\n\n", "name", "age", "sex", "tele", "addr");
printf("%15s\t%5d\t%8s\t%15s\t%30s\n",
ps->data[pos].name,
ps->data[pos].age,
ps->data[pos].sex,
ps->data[pos].tele,
ps->data[pos].addr);
}
}
}10. Modify the designated contact
Method: enter the name of the contact to be searched, call the search function to search, find the returned corresponding subscript, and then modify the content of the corresponding array subscript
void ModifyContact(struct Contact* ps)
{
char name[NAME_MAX] = { 0 };
printf("Please enter the name of the person to modify:>");
scanf("%s", name);
int pos = FindContactByName(ps, name);
if (-1 == pos)
{
printf("No one was found\n");
}
else
{
printf("Please enter a new name:");
scanf("%s", ps->data[pos].name); //Array name is not used&
printf("Please enter a new age: ");
scanf("%d", &(ps->data[pos].age));
printf("Please enter a new address:");
scanf("%s", ps->data[pos].addr);
printf("Please enter a new number:");
scanf("%s", ps->data[pos].tele);
printf("Please enter a new gender:");
scanf("%s", ps->data[pos].sex);
}
}
11. Sort contacts by name
Equivalent to string comparison - > using strcmp
Two methods can be used here: bubble sort or qsort sort
About qsort: Detailed explanation of qsort function
Compare the member names in the address book member array!!!
void SortContact(struct Contact* pcon)
{
int i, j;
struct PeoInfo tmp;
for(i = 0; i < pcon->sz - 1; i++)
{
for(j = 0; j < pcon->sz - 1 - i; j++)
{
if(0 < strcmp(pcon->data[j].name, pcon->data[j + 1].name))
{
tmp = pcon->data[j];
pcon->data[j] = pcon->data[j + 1];
pcon->data[j + 1] = tmp;
}
}
}
}void SortContactByName(struct Contact* ps)
{
qsort(ps->data, ps->size, sizeof(ps->data[0]), cmp_ContactByName);
}
int cmp_ContactByName(const void* e1, const void* e2)
{
return strcmp( ((struct PeoInfo*)e1)->name, ((struct PeoInfo*)e2)->name);
}
//be careful
// ((struct peoinfo *) e1) - > name should be enclosed,
// (struct peoinfo *) e1 - > name is wrong12. Sort contacts by age
Note that the member array PS - > data in the address book is sorted: the type of each element is struct PenInfo (structure member type), and the number to be sorted is PS - > size
The size flag indicates the number of address book members
Comparison function: the age of members is compared
void SortContact(struct Contact* ps)
{
qsort(ps->data, ps->size, sizeof(ps->data[0]), cmp_ContactbyAge);
}
int cmp_ContactbyAge(const void* e1, const void* e2)
{
return ((struct PeoInfo*)e1)->age - ((struct PeoInfo*)e2)->age;
}13. Empty the address book
Empty address book: equivalent to reinitialization of heap address book
void ClearContact(Contact* pcon)
{
InitContact(pcon);
}3, Disadvantages of static address book
Limited membership: it is easy to cause space waste / insufficient space.
In order to solve this problem, in the next article, bloggers will take you to learn about dynamic address book
Thank you very much for seeing here, ~ if it helps you, welcome to give the blogger a three company~