Imports System.Data.SQLite Public Class DbManager ' Adjust connection string based on your database file location Private Shared connString As String = "Data Source=BillingDB.db;Version=3;" Public Shared Function GetConnection() As SQLiteConnection Dim conn As New SQLiteConnection(connString) Return conn End Function ' Setup initial sample tables if they do not exist Public Shared Sub InitializeDatabase() Using conn As SQLiteConnection = GetConnection() conn.Open() Dim cmdText As String = " CREATE TABLE IF NOT EXISTS Products ( ProductID INTEGER PRIMARY KEY AUTOINCREMENT, ProductName TEXT NOT NULL, Price DECIMAL(10,2), StockQuantity INTEGER ); CREATE TABLE IF NOT EXISTS Invoices ( InvoiceID INTEGER PRIMARY KEY AUTOINCREMENT, InvoiceDate DATETIME, CustomerName TEXT, GrandTotal DECIMAL(10,2) ); CREATE TABLE IF NOT EXISTS InvoiceDetails ( DetailID INTEGER PRIMARY KEY AUTOINCREMENT, InvoiceID INTEGER, ProductID INTEGER, Quantity INTEGER, UnitPrice DECIMAL(10,2), SubTotal DECIMAL(10,2) );" Using cmd As New SQLiteCommand(cmdText, conn) cmd.ExecuteNonQuery() End Using End Using End Sub End Class Use code with caution. 2. Main Billing Form Logic ( frmBilling.vb )
Public Sub OpenConnection() ' Change Data Source according to your SQL Server instance conn = New SqlConnection("Data Source=.\SQLEXPRESS;Initial Catalog=BillingDB;Integrated Security=True") If conn.State = ConnectionState.Closed Then conn.Open() End If End Sub
Implement a Suggest mode in your product name textbox to pull data from your database as the user types. vbnet+billing+software+source+code
Private Async Function LoadProductsAsync() As Task ' Asynchronous database retrieval routine End Function Use code with caution.
The complete source code behind frmBilling.vb manages calculations, line-item additions, inventory checks, and final multi-table database insertions inside a transaction block. Imports System
Just remember: . Audit security, add parameterized queries, and for God’s sake, move the connection string out of the form load event.
: Use SQL Server or MS Access to store product lists, customer details, and transaction history. User Interface DataGridView to display items in the current bill, inputs for quantities/prices, and a to process the sale. Calculation Logic Audit security, add parameterized queries, and for God’s
Generate professional receipts and invoices that can be printed or exported to formats like Excel , Word , or PDF using tools like Crystal Reports .
Stores high-level summary information for every transaction. InvoiceNo (AutoNumber, Primary Key) InvoiceDate (Date/Time) CustomerName (Short Text) SubTotal (Currency) TaxAmount (Currency) GrandTotal (Currency) 3. Invoice Details Table ( InvoiceDetails )