1. Demand analysis

Using C + + to realize address book management system

The following functions need to be realized in the system:

Add contact: add a new contact to the address book. The information includes (name, gender, age, contact number, home address, and records up to 1000 people.

Show contacts: displays all contact information in the address book

Delete contact: delete the specified contact by name

Find contact: find the specified contact by name

Modify contact: modify the specified contact according to the name

Empty contact: clear all information in the address book

Exit address book: exit the currently used address book

2. Create project

The steps to create a project are as follows:

· create a new project

· add files

2.1 create a new project

2.2 adding files

 

 

 3. Menu function

Function Description: the interface for users to select functions

The menu effect diagram is as follows:

Steps:

·The encapsulated function void showmenu() displays this interface

Calling display function in main function

Reference code:

void showMenu()
{
	cout << "*****************************" << endl;
	cout << "*****	1.Add a Contact 	*****" << endl;
	cout << "*****	2.Show contacts	*****" <<endl;
	cout << "*****	3.Delete Contact 	*****" << endl;
	cout << "*****	4.find contact 	*****" << endl;
	cout << "*****	5.Modify contact	*****" << endl;
	cout << "*****	6.Empty contacts	*****" << endl;
	cout << "*****	0.Exit address book	*****" << endl;
	cout << "*****************************" << endl;
}


int main()
{
	//Menu call
	showMenu();

	system("pause");
	return 0;
}

4. Exit function

Function Description: exit the address book system

Idea: enter different functions according to different choices of users, and build the framework through switch branch structure

Reference code:

int main()
{	
	//Create user selected variables
	int select = 0; 
	while (true)
	{
		//Menu call
		showMenu();
		cin >> select;

		switch (select)
		{
		case 1://Add a Contact 
			break;

		case 2://Show contacts
			break;

		case 3://Delete Contact 
			break;

		case 4://find contact 
			break;

		case 5://Modify contact
			break;

		case 6://Empty contacts
			break;

		case 0://Exit address book
			cout << "Welcome to use again!" << endl;
			system("pause");
			return 0;
			break;

		default:
			break;
		}

	}	
	system("pause");
	return 0;
}

5. Add contact

Function Description: realize the function of adding contacts, and the upper limit of contacts is 1000; Contact information includes (name, gender, age, contact number, home address)

Steps:

·Design contact structure

·Design address book structure

·Create address book in main function

·Encapsulate add contact function

·Test add contact function

5.1 design contact structure

Contact information includes: name, gender, age, contact number, home address

Reference code:

struct person
{
	string m_Name; //full name
	int m_Sex; //Gender: 1 male, 2 female
	int m_Age;//Age
	string m_Phone; //Telephone
	string m_Addr; //Home address
};

5.2 design address book structure

The maximum number is 1000, and the number of existing contacts is recorded

Reference code:

#define MAX 1000 / / maximum number of people
//Address book structure
struct addressbooks
{
	struct person personArray[MAX];	//An array of contacts saved in the address book
	int m_size ;	//Number of people already in the address book
};

5.3 create address book in main function

After the add contact function is encapsulated, create an address book variable in the main function, which is the address book that needs to be maintained all the time.

Reference code:

//Create address book structure variable
Addressbooks abs;
//Initialize the number of people in the address book
abs.m_size = 0;
	

5.4 encapsulating and adding contact functions

Idea: first, check whether the address book is full. If it is full, you cannot continue to add it. If it is not full, enter the contact data one by one

Reference code:

//Add a Contact 
void addPerson(Addressbooks * abs)
{
	//Judge whether the address book is full. If it is full, it will not be added
	if (abs->m_size == MAX)
	{
		cout << "The address book is full and cannot be added" << endl;
		return;
	}
	else  //Add specific contacts
	{
		//full name
		cout << "Please enter your name" << endl;
		string name;
		cin >> name;
		abs->personArray[abs->m_size].m_Name = name;
		//Gender
		cout << "Please enter gender:" << endl;
		cout << "1 -- male" << endl;
		cout << "2 -- female" << endl;
		int sex = 0;
		while (true)
		{
			//If you enter 1 or 2, you can exit the cycle. If the input is wrong, you can re-enter it
			cin >> sex;
			if (sex == 1 || sex == 2)
			{
				abs->personArray[abs->m_size].m_Sex;
				break;
			}
			cout << "Input error, please re-enter" << endl;
		}
		//Age
		cout << "Please enter age" << endl;
		int age = 0;
		cin >> age;
		abs->personArray[abs->m_size].m_Age = age;
		//contact number
		cout << "Please enter the contact number" << endl;
		string phone;
		cin >> phone;
		abs->personArray[abs->m_size].m_Phone = phone;
		//Home address
		cout << "Please enter your home address" << endl;
		string address;
		cin >> address;
		abs->personArray[abs->m_size].m_Addr = address;
		//Number of contacts updated
		abs->m_size++;
		cout << "Added successfully" << endl;
		system("pause"); //Please press any key to continue
		system("cls");//Clear screen
	}
}

5.5 test add contact function

Select 1 in the selection interface to add a contact

Add in switch statement

case 1://Add a Contact 
	addPerson(&abs);
	break;

design sketch

 6. Show contacts

Function Description: displays the existing contact information in the address book

Steps:

· encapsulate and display contact function

· test and display contact function

6.1 encapsulated display contact function

Idea: when there is no one in the current address book, it will prompt that the address book is empty and the number of people is greater than 0 to display the information in the address book

Reference code:

//Show contact function
void showPerson(Addressbooks * abs)
{
	//Judge whether the address book is empty. If it is empty, it will prompt that the address book is empty
	//If it is not empty, the circular output information
	if (abs->m_size == 0)
	{
		cout << "Current address book is empty" << endl;
	}
	else
	{
		for (int i = 0; i < abs->m_size; i++)
		{
			cout << "full name:" << abs->personArray[i].m_Name << "\t";
			cout << "Gender:" << (abs->personArray[i].m_Sex == 1?"male":"female") << "\t";
			cout << "Age:" << abs->personArray[i].m_Age << "\t";
			cout << "contact number:" << abs->personArray[i].m_Phone << "\t";
			cout << "Home address:" << abs->personArray[i].m_Addr << endl;

		}
	}
	system("pause"); //press any key to continue
	system("cls");//Clear screen
}

6.2 test and display contact function

In the switch case statement, add the following to case2:

case 2://Show contacts
	showPerson(&abs);
	break;

design sketch

 7. Delete Contact

Function Description: delete the specified contact by name

Steps:

·Encapsulates a function that detects whether a contact exists

·Encapsulate delete contact function

·Test delete contact function

7.1 whether the package inspection contact exists

Design idea: before deleting a contact, judge whether the contact entered by the user exists. If it exists, return to the location and delete it. If it does not exist, return - 1

Reference code:

//Check whether the contact exists. If it exists, return the specific subscript position. If it does not exist, return - 1
int isExist(Addressbooks * abs,string name)
{
	for (int i = 0; i < abs->m_size; i++)
	{
		//If found, return the subscript i
		if (abs->personArray[i].m_Name == name)
		{
			return i; 
		}	
	}
	return -1;
}

7.2 encapsulating and deleting contact function

Design idea: according to the search function, if it is found, it will be deleted; if it is not found, it will prompt that there is no such person

Reference code:

//Delete specified contact
void deletePerson(Addressbooks* abs)
{
	cout << "Please enter the name of the contact you want to delete" << endl;
	string name;
	cin >> name;
	//ret == -1, not found; ret != -1. I found it
	int ret=isExist(abs, name);
	if (ret != -1)
	{
		//Found, delete
		for (int i = ret; i < abs->m_size; i++)
		{	
			//Data forward
			abs->personArray[i] = abs->personArray[i + 1];
		}
		abs->m_size--;//Number of contacts updated
		cout << "Delete succeeded!" << endl;
	}
	else
	{
		cout << "No one was found" << endl;
	}
	system("pause");//press any key to continue
	system("cls");//Clear screen
}

7.3 test the function of deleting contacts

In the switch case statement, case3 adds:

case 3://Delete Contact 
	deletePerson(&abs);
	break;

design sketch

 

8. Find contacts

Function Description: view the specified contact information by name

Steps:

·Encapsulate find contact function

·Test function function

8.1 encapsulating the contact lookup function

Idea: judge whether the contact specified by the user exists, whether there is display information, and whether there is no prompt. Check whether there is no such person.

Reference code:

//find contact 
void findPerson(Addressbooks * abs)
{
	cout << "Please enter the contact you want to find" << endl;
	string name;
	cin >> name;

	int ret = isExist(abs, name);
	if (ret != -1)
	{
		cout << "full name:" << abs->personArray[ret].m_Name << "\t";
		cout << "Gender:" << (abs->personArray[ret].m_Sex == 1?"male":"female") << "\t";
		cout << "Age:" << abs->personArray[ret].m_Age << "\t";
		cout << "contact number:" << abs->personArray[ret].m_Phone << "\t";
		cout << "Home address:" << abs->personArray[ret].m_Addr << endl;
	}
	else
	{
		cout << "No one was found" << endl;
	}
	system("pause");
	system("cls");
}

8.2 test the function of finding contacts

In the switch case statement, add the following to case4:

case 4://find contact 
	findPerson(&abs);
	break;

design sketch

 9. Modify contact

Function Description: re modify the specified contact according to the name

Steps:

·Encapsulating and modifying contact functions

·Test function function

9.1 encapsulating and modifying contact functions

Idea: find the contact entered by the user. If the search is successful, modify it, and if the search fails, you will be prompted that there is no such person

Reference code:

//Modify contact
void modifyPerson(Addressbooks* abs)
{
	cout << "Please enter the contact name you want to modify" << endl;
	string name;
	cin >> name;
	int ret = isExist(abs, name);
	if (ret != -1)
	{
		//Modify name
		cout << "Please enter your name" << endl;
		string name;
		cin >> name;
		abs->personArray[ret].m_Name = name;
		//Modify gender
		cout << "Please enter gender\n1 -- male\n2 -- female" << endl;
		int sex;
		cin >> sex;
		while (true)
		{
			if (sex == 1 || sex == 2)
			{
				abs->personArray[ret].m_Sex = sex;
				break;
			}
			else
			{
				cout << "Please re-enter" << endl;
			}
		}
		//Modify age
		int age = 0;
		cout << "Please enter age" << endl;
		cin >> age;
		abs->personArray[ret].m_Age = age;
		//Modify contact number
		cout << "Please enter the contact number" << endl;
		string phone;
		cin >> phone;
		abs->personArray[ret].m_Phone = phone;
		//Modify home address
		cout << "Please enter your home address" << endl;
		string address;
		cin >> address;
		abs->personArray[ret].m_Addr = address;
		cout << "Modified successfully" << endl;
	}
	else
	{
		cout << "No one was found" << endl;
	}
	system("pause");
	system("cls");
}

9.2 test and modify contact function

In the switch case statement, add the following to case5:

case 5://Modify contact
	modifyPerson(&abs);
	break;

design sketch

10. Empty contacts

Function Description: clear all information in the address book

Steps:

·Encapsulate empty contact function

·Test the function of clearing contacts

10.1 encapsulate empty contact function

Idea: just set the number of contacts to 0

Reference code:

//Empty contacts
void cleanPerson(Addressbooks* abs)
{
	cout << "Are you sure to clear the address book?\n1.determine\n2.cancel" << endl;
	int flag = 0;
	while (true)
	{
		cin >> flag;
		if (flag == 1)
		{
			abs->m_size = 0;
			cout << "Contacts to empty" << endl;
			break;
		}
		else if (flag == 2)
		{
			cout << "Cancelled, address book not empty" << endl;
			break;
		}
		else
		{
			cout << "Input error, please re-enter" << endl;
		}
	}
	system("pause");//press any key to continue
	system("cls");//Clear screen
}

10.2 test the function of clearing contacts

In the switch case statement, add the following to case6:

case 6://Empty contacts
	cleanPerson(&abs);
	break;

design sketch