C++实现登录注册，并将数据保存到文件（txt文档中）

实现要求：
1.如果不存在初始用户数据文件则创建用户数据文件
2.实现完整的注册登录
3.实现用户数据的自动保存和读取
4.密码输入提供直接显示和隐式显示

1.运行截图

运行结果如下：

2.实现代码

代码如下：

#include "iostream"
#include "fstream"
#include "string"
#include <conio.h>
using namespace std;

#define SIZE 100//最大用户容量
int scount = 0;//用作储存当前已注册用户数

//用户类
class User
{
    
private:
	string phone;//电话
	string password;//密码
public:
	User() {
    };
	void Registers();//注册
	void Login();//登录
	void save();//保存
	void read();//读取
}us;

User user[SIZE];

//保存
void User::save()
{
    
	ofstream ofile;
	ofile.open("user.txt", ios::out);

	for (int i = 0; i < scount; i++)
	{
    
		ofile << user[i].phone << endl;
		ofile << user[i].password << endl;
	}
	ofile.close();
}

//读取
void User::read()
{
    
	ifstream ifile;
	ifile.open("user.txt", ios::in);

	scount = 0;

	if (!ifile.is_open())
	{
    
		//cout << "文件打开失败！" << endl;
		return;
	}

	for (int i = 0; !ifile.eof(); i++)
	{
    
		ifile >> user[i].phone;
		ifile >> user[i].password;
		scount++;
	}
	scount--;
	ifile.close();
}

//注册
void User::Registers()
{
    
	us.read();//读取已储存用户数据
	string ph;//电话
	string pw1;//密码1
	string pw2;//密码2
	for (int i = scount; i < SIZE; i++)
	{
    
	here:
		cout << "\t\t\t【系统提示】请输入手机号：";
		cin >> ph;
		//判断新输入的用户信息是否已存在（如果已存在则重新输入）
		for (int i = 0; i < scount; i++)
		{
    
			if (ph == user[i].phone)
			{
    
				cout << "\t\t\t【系统提示】用户已存在！" << endl;
				goto here;
			}
		}
		user[i].phone = ph;

		int chose = -1;
		cout << endl;
		cout << "\t\t\t┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓\n";
		cout << "\t\t\t┃       1.显示密码     2.隐藏密码      ┃\t\n";
		cout << "\t\t\t┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛\n";
		cout << "\t\t\t【系统提示】请输入你的选择：";
		cin >> chose;
		if (chose > 2 || chose < -1)
		{
    
			cout << "\t\t\t【系统提示】输入格式错误，请重新输入：";
			cin >> chose;
		}

		string pword;
		char ch, passwords0[20];
		int x = 0;
		string pword1;
		char ch1, passwords1[20];
		int x1 = 0;
		switch (chose)
		{
    
		case 1:
			cout << "\t\t\t【系统提示】请输入密码：";
			cin >> pword;
			user[i].password = pword;
			cout << "\t\t\t【系统提示】请再次密码：";
			cin >> pword1;
			if (pword1 != user[i].password)
			{
    
				cout << "\t\t\t【系统提示】密码不一致！" << endl;
				goto here;
			}
			else
			{
    
				scount++;//已注册用户加1
				cout << "\t\t\t【系统提示】注册成功！" << endl;
				us.save();//保存用户数据
			}
			break;
		case 2:
			cout << "\t\t\t【系统提示】请输入密码：";
			while ((ch = _getch()) != '\r' && x <= 20)
			{
    
				if (ch == '\b')
				{
    
					if (x > 0)
					{
    
						x--;
						cout << "\b \b";//密码支持退格的实现
					}
					else
						putchar(7);
				}
				else
				{
    
					passwords0[x++] = ch;
					printf("*");
				}
			}
			passwords0[x] = '\0';
			cout << endl;
			user[i].password = passwords0;

			cout << "\t\t\t【系统提示】请再次密码：";
			while ((ch1 = _getch()) != '\r' && x1 <= 20)
			{
    
				if (ch1 == '\b')
				{
    
					if (x1 > 0)
					{
    
						x1--;
						cout << "\b \b";//密码支持退格的实现
					}
					else
						putchar(7);
				}
				else
				{
    
					passwords1[x1++] = ch1;
					printf("*");
				}
			}
			passwords1[x1] = '\0';
			cout << endl;
			//比较两次输入的密码是否统一（如果不统一则重新输入）
			if (passwords1 != user[i].password)
			{
    
				cout << "\t\t\t【系统提示】密码不一致！" << endl;
				goto here;
			}
			else
			{
    
				scount++;//已注册用户加1
				cout << "\t\t\t【系统提示】注册成功！" << endl;
				us.save();//保存用户数据
			}
			break;
		}
		char choice;
		cout << "\t\t\t【系统提示】是否继续注册(Y/N)？ :";
		while (1)
		{
    
			cin >> choice;
			if (choice == 'y' || choice == 'Y' || choice == 'n' || choice == 'N')
				break;
			else
				cout << "\t\t\t【系统提示】输入格式错误，请重新输入： ";
		}
		if (choice == 'n' || choice == 'N')
		{
    
			break;
		}
	}
}

//登录
void User::Login()
{
    
	us.read();//读取已储存用户数据
	string ph;//电话
	string pw;//密码
	int time = 0;//统计比较次数
here:
	cout << "\t\t\t【系统提示】请输入手机号：";
	cin >> ph;
	int chose = -1;
	cout << endl;
	cout << "\t\t\t┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓\n";
	cout << "\t\t\t┃       1.显示密码     2.隐藏密码      ┃\t\n";
	cout << "\t\t\t┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛\n";
	cout << "\t\t\t【系统提示】请输入你的选择：";
	cin >> chose;
	if (chose > 2 || chose < -1)
	{
    
		cout << "\t\t\t【系统提示】输入格式错误，请重新输入：";
		cin >> chose;
	}

	string pword;
	char ch, passwords0[20];
	int x = 0;
	switch (chose)
	{
    
	case 1:
		cout << "\t\t\t【系统提示】请输入密码：";
		cin >> pword;
		for (int i = 0; i < scount; i++)
		{
    
			if (ph == user[i].phone && pword == user[i].password)
			{
    
				time++;
				//cout << "\t\t\t【系统提示】登录成功！" << endl;
			}
		}
		if (time == 0)
		{
    
			cout << "\t\t\t【系统提示】手机号或密码错误！" << endl;
			goto here;
		}
		break;
	case 2:
		cout << "\t\t\t【系统提示】请输入密码：";
		while ((ch = _getch()) != '\r' && x <= 20)
		{
    
			if (ch == '\b')
			{
    
				if (x > 0)
				{
    
					x--;
					cout << "\b \b";//密码支持退格的实现
				}
				else
					putchar(7);
			}
			else
			{
    
				passwords0[x++] = ch;
				printf("*");
			}
		}
		passwords0[x] = '\0';
		cout << endl;
		//依次比较已储存信息，比较是否匹配（如不匹配则提示错误）
		for (int i = 0; i < scount; i++)
		{
    
			if (ph == user[i].phone && passwords0 == user[i].password)
			{
    
				time++;
				cout << "\t\t\t【系统提示】登录成功！" << endl;
			}
		}
		if (time == 0)
		{
    
			cout << "\t\t\t【系统提示】手机号或密码错误！" << endl;
			goto here;
		}
		break;
	}
}

int main()
{
    
	User user;
	int chose = -1;
	cout << endl;
	cout << "\t\t\t┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓\n";
	cout << "\t\t\t┃       1.注    册     2.登    录      ┃\t\n";
	cout << "\t\t\t┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛\n";
	cout << "\t\t\t【系统提示】请输入你的选择：";
	cin >> chose;
	if (chose > 2 || chose < -1)
	{
    
		cout << "\t\t\t【系统提示】输入格式错误，请重新输入：";
		cin >> chose;
	}
	switch (chose)
	{
    
	case 1:user.Registers(); break;
	case 2:user.Login(); break;
	}
}

代码小白，仅作学习记录