🏦 Bank Management System in C++

A menu-driven Bank Management System developed in C++ using Object-Oriented Programming (OOP) concepts. The application supports customer registration, account creation, deposits, withdrawals, account details, and transaction history.

The project uses file handling to store data locally in bank_data.txt, allowing saved records to be loaded when the application runs again.

📌 Features

• Customer Management

  • Create new customers.
  • Display registered customers.
  • Validate phone numbers.
  • Prevent duplicate phone numbers.

• Account Management

  • Create savings accounts.
  • Create current accounts.
  • View account details and balances.
  • Display all active accounts.
  • Close accounts when their balance is zero.
  • Prevent reuse of previously used account numbers.

• Banking Operations

  • Deposit money.
  • Withdraw money.
  • Validate transaction amounts.
  • Check account ownership during supported operations.

• Transaction Management

  • Maintain transaction records.
  • View transaction history for an account.
  • Display transaction receipts.

• File Handling

  • Save customer and account information.
  • Store transaction records.
  • Load saved data when the program starts.

🛠️ Technologies Used

Technology	Purpose
C++	Core programming language
Object-Oriented Programming	Application design
File Handling	Local data persistence
Standard Template Library (STL)	Data structures and collections
Command-Line Interface	User interaction

🧠 OOP Concepts Demonstrated

1. Encapsulation

Classes manage their data through member functions and controlled access.

2. Inheritance

SavingsAccount and CurrentAccount inherit common account functionality from the abstract Account class.

3. Abstraction

The Account class defines a common interface and declares withdraw() as a pure virtual function.

4. Polymorphism

Different account types implement the withdraw() function according to their account-specific behavior.

5. Classes and Objects

The project uses classes such as Customer, Account, SavingsAccount, CurrentAccount, Transaction, and Bank.

6. Static Data Members

A static counter is used for customer ID generation.

🏗️ Project Structure

Bank-Management-System/
├── main.cpp
├── bank_data.txt
└── README.md

Note: Replace main.cpp with your actual C++ source filename. The bank_data.txt file is used at runtime for local data storage and does not need to be committed unless you want to include sample data.

⚙️ Installation and Execution

Prerequisites

• A C++ compiler such as GCC/G++.
• A terminal or IDE, such as Visual Studio Code.

Step 1: Clone the Repository

git clone https://github.com/VishalTech45/Bank-Management-System.git
cd Bank-Management-System

Step 2: Compile the Program

Replace main.cpp with your actual source filename.

g++ -std=c++17 main.cpp -o bank

Step 3: Run the Program

Windows — PowerShell or Command Prompt

.\bank.exe

Linux / macOS

./bank

📋 Application Menu

Option	Operation
1	Create Customer
2	Create Savings Account
3	Create Current Account
4	Deposit Money
5	Withdraw Money
6	Check Account Balance / Details
7	Display All Accounts
8	View Transaction History
9	Close Account
10	Display All Customers
0	Exit

Select an option and follow the on-screen instructions.

💾 Data Storage

The application stores data locally in bank_data.txt.

The file preserves information such as:

• Customer records
• Active account records
• Previously used account numbers
• Transaction records

The program loads saved data when it starts and saves data through its file-persistence functionality.

Important: Keep the data file in the location expected by the application. Back it up if you want to preserve your records.

This is a local file-based application. It does not currently use PostgreSQL or another database.

✅ Validation and Error Handling

The current implementation includes checks for:

• Phone numbers containing exactly 10 digits.
• Duplicate customer phone numbers.
• Invalid or non-positive transaction amounts.
• Account ownership during supported operations.
• Account closure only when the balance is zero.
• Reuse of previously assigned account numbers.

⚠️ Current Limitations

• Data is stored in a local text file rather than a database.
• Monetary values use double, which can introduce floating-point precision issues.
• The application uses a console-based interface.
• Login/PIN authentication is not currently implemented.
• Online banking, fund transfers, and overdraft facilities are not implemented.
• The interest calculation is basic and does not represent a complete real-world banking policy.

🚀 Future Improvements

Potential enhancements for future versions include:

• Integrating PostgreSQL for structured data storage.
• Using integer paise for more reliable monetary calculations.
• Adding secure authentication and role-based access.
• Implementing fund transfers between accounts.
• Improving transaction consistency and error handling.
• Adding account statements and financial reports.
• Developing a graphical user interface or REST API.
• Adding automated unit tests.

These are proposed enhancements, not features currently implemented.

🎯 Learning Objectives

This project demonstrates practical applications of:

• C++ classes and objects
• Inheritance and polymorphism
• Abstract classes and virtual functions
• Encapsulation and abstraction
• Pointers and object management
• Input validation
• File handling and data persistence
• Menu-driven program design

👨‍💻 Author

Vishal Kumar

📄 License

No specific open-source license is included unless a LICENSE file is added to the repository.

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Disclaimer: This is an educational banking simulation and is not intended for real banking or financial transactions.