Description

This project is a comprehensive banking simulation system built entirely in C++ as a console-based application. It is divided into two interconnected programs:

  1. Bank System (Employee-Facing): Used by bank staff to manage clients, users, transactions, and system settings.
  2. ATM Simulation (Client-Facing): Used by clients to perform typical banking operations like withdrawals, deposits, transfers, and checking balances.

Both applications share the same underlying storage files to ensure consistent data handling. Together, they simulate a real-world banking ecosystem with both administrative and customer-facing operations.

Technologies Used

  • C++ (Standard 11/14) — Core language for implementation.
  • Standard Library Features:
    • <fstream> for file handling.
    • <vector> for dynamic data structures.
    • <iomanip> for formatted output.
    • <ctime> for time/date stamping.
    • <sstream> for parsing and formatting.
  • Console-Based UI with menu-driven navigation.
  • File-Based Persistent Storage for clients, users, messages, history, and system settings.

Functionality / Features (High-Level)

Bank System (Employee-Facing)

  • Client Management: Add, update, delete, lock/unlock, and search clients.
  • User Management: Create, update, delete, and manage permissions for employees.
  • Transactions: Deposit, withdraw, calculate total balances, and review transaction histories.
  • History Tracking: Full audit trail for every client action (deposits, withdrawals, updates, etc.).
  • Messaging System: Employees can send and clear messages for clients (viewable at ATM).
  • Settings Management: Customize tables (fields visibility) and text/background colors.
  • Security Features: Account locking/unlocking, PIN code management.

ATM Simulation (Client-Facing)

  • Login System with PIN-based authentication and limited login trials.
  • Quick Withdraw Options (pre-set amounts like 20, 50, 100, etc.).
  • Normal Withdraw (custom amounts with validation).
  • Deposits & Transfers with balance checks and confirmation prompts.
  • Account History: Clients can review past transactions.
  • Messaging: Clients can receive messages from bank staff.
  • Profile Updates: Change phone number and PIN securely.
  • Balance Inquiry: Real-time account balance display.
  • Account Lock Handling: Locked accounts prompt users to contact the bank.

Implementation Highlights

File-Based Persistent Storage

Both the Bank System and ATM use plain text files (Clients.txt, Users.txt, History.txt, Messages.txt, Settings.txt) to maintain data consistency.

  • Data is serialized with a custom delimiter (#//#) for safe parsing.
  • Each program has its own conversion functions (convertClientLineToRecord, convertClientRecordToLine, etc.) that transform between human-readable lines and structured structs like sClient or sUser.
  • This design eliminates the need for external databases, while still mimicking how databases store and retrieve structured records.

🔹Portfolio Value: Shows mastery of low-level data persistence and careful structuring without relying on ORM or external DB tools.

Client Management & Validation (Bank System)

  • Employees can add, update, delete, search, and lock/unlock client accounts.
  • Input validation is robust — phone numbers, names, and PIN codes are strictly checked for length, numeric count, and formatting.
  • Account numbers are checked for uniqueness before adding new clients.

🔹Portfolio Value: Demonstrates a solid grasp of input validation, data integrity, and edge-case handling.

User Management & Permissions (Bank System Only)

  • Employees (users) are stored separately in Users.txt.
  • Permissions are encoded with bitmasking techniques, allowing fine-grained control (e.g., full access vs. partial permissions for client/user management).
  • Active user is always tracked, and unauthorized actions trigger “Access Denied” screens.

🔹Portfolio Value: Highlights understanding of role-based access control (RBAC) and encoding permissions efficiently.

Transactions (Both Programs)

  • ATM: Clients can deposit, withdraw (quick or normal), and transfer money.
  • Bank System: Employees can also deposit and withdraw on behalf of clients, plus calculate total balances across all accounts.
  • Every transaction updates:
    • Client balance
    • Modification timestamp (dateModified)
    • History file (History.txt) with the action type (Deposit, Withdraw, Transfer, etc.)

🔹Portfolio Value: Shows ability to design stateful operations with audit trails and consistent file updates.

Transaction History & Audit Trail (Both)

  • Every client has a dedicated history log embedded in History.txt.
  • Records store date, PIN, name, phone, balance, and action type (via enum enClientUpdateType).
  • Bank employees can pull client histories for auditing.
  • Clients themselves can review their transaction history via the ATM.

🔹Portfolio Value: Demonstrates auditing, logging, and accountability — crucial in financial systems.

Messaging System (Cross-Program)

  • Bank System: Employees can send or clear messages tied to specific accounts.
  • ATM: Clients can read their messages during login sessions. Messages support multi-line input (via \n escape handling).
  • This simulates real-world bank-to-client communication (e.g., warnings, updates, promotions).

🔹Portfolio Value: Shows understanding of inter-system communication and multi-program coordination.

Security Features

  • PIN Code Management: Clients can change their PIN securely at the ATM.
  • Phone Number Update: Clients can update their personal info with validation.
  • Account Locking:
    • Automatic: Account locks after three consecutive failed login attempts at the ATM.
    • Manual: Bank employees can lock/unlock accounts through the Bank System.
  • Audit Trail: All security changes (PIN updates, locks/unlocks) are logged in the history file.

🔹Portfolio Value: Reflects thoughtfulness around data protection and fraud prevention, even at a simulation level.

Customizable System Settings (Bank System)

  • Table views (clients/users) can be customized: fields shown/hidden are controlled via bitmask flags.
  • Text/background color customization via encoded settings in Settings.txt.
  • Default settings auto-populate if missing.

🔹Portfolio Value: Shows foresight into configurable systems and a taste for usability.

Console UI & Navigation (Both)

  • Menu-driven interface with clear headers, separators, and consistent design.
  • ATM: Focused on user-friendliness, minimal options, and confirmations.
  • Bank System: More advanced with sub-menus for clients, users, transactions, settings.
  • Operation Cancelation: Entering -99 cancels most operations (withdrawals, deposits, searches, etc.), letting users back out without disrupting the system.
  • Confirmation Prompts: Before critical actions (like withdrawals, deposits, transfers, or deletions), users must explicitly confirm with [Y] - [N].
  • Clear Console Navigation: Consistent menu-driven flow with screen clearing (system("cls")) and pauses for readability.

🔹Portfolio Value: While console-based, the UI is thoughtfully crafted to mimic user experience design principles.

Conclusion

  • Built a two-part banking ecosystem (Bank System + ATM) sharing the same storage, simulating real-world banking workflows.
  • Implemented file-based persistence with custom serialization and parsing logic.
  • Added robust client and user management features, including fine-grained permission control.
  • Ensured transaction integrity with real-time balance updates and a full audit trail in History.txt.
  • Integrated a messaging system bridging employees and clients.
  • Enhanced security via PIN changes, account locking, and strict input validation.
  • Designed a customizable console UI with configurable tables and color settings for usability.

Screenshots

Bank System

Main Menu Screen
Manage Clients Screen
Clients List Screen
Find Client Screen
Change Background Color Screen
Update User Info Screen
Access Denied Screen

ATM

Client Login Screen
Main Menu Screen
Quick Withraw Screen
Transfer Money Screen
Account Locked Screen

Try the Project

  • You can download the executable files for both Bank System & ATM from here.
  • Please note that the default username is "Admin", with the password "1234".

Since this application is not digitally signed by a recognized publisher, your system may display a warning before running it. You can safely ignore it and continue.

Source code

You can find the source code for both Bank System & ATM here.

Updated: