Vb.net Billing Software Source Code

Module mod_DB Public connString As String = "Data Source=localhost\SQLEXPRESS;Initial Catalog=BillingDB;Integrated Security=True"

' Execute a query Dim cmd As New OleDbCommand("SELECT * FROM Products", conn) Dim reader As OleDbDataReader = cmd.ExecuteReader()

In the world of desktop application development, remains a surprisingly robust and efficient choice for building business applications, particularly billing and invoicing systems. Its rapid application development (RAD) environment, seamless integration with the .NET framework, and ease of database connectivity make it an ideal language for creating point-of-sale (POS) systems, retail billing software, and service invoicing tools. vb.net billing software source code

' Check if product already in cart Dim existingRow As DataRow() = dtCart.Select("ProductID = " & productID) If existingRow.Length > 0 Then existingRow(0)("Quantity") = CInt(existingRow(0)("Quantity")) + quantity existingRow(0)("Total") = CDec(existingRow(0)("Quantity")) * unitPrice Else dtCart.Rows.Add(productID, productCode, productName, quantity, unitPrice, gst, total) End If

Private Sub btnRemoveFromCart_Click(sender As Object, e As EventArgs) Handles btnRemoveFromCart.Click If dgvCart.CurrentRow IsNot Nothing Then dtCart.Rows.RemoveAt(dgvCart.CurrentRow.Index) UpdateGrandTotal() End If End Sub Module mod_DB Public connString As String = "Data

: Implements foreign key constraints between products, customers, and invoice tables.

' 1. Header Layout blockgraphicEngine.DrawString("ENTERPRISE RETAIL STORE", fontHeader, Brushes.Black, coordinateX, coordinateY)coordinateY += 30graphicEngine.DrawString("Invoice ID: " & ActiveInvoiceID.ToString(), fontNormal, Brushes.Black, coordinateX, coordinateY)coordinateY += rowOffsetgraphicEngine.DrawString("Date: " & DateTime.Now.ToString("g"), fontNormal, Brushes.Black, coordinateX, coordinateY)coordinateY += rowOffsetgraphicEngine.DrawString("Customer: " & txtCustomerName.Text, fontNormal, Brushes.Black, coordinateX, coordinateY)coordinateY += 35graphicEngine.DrawString("-----------------------------------------------------", fontNormal, Brushes.Black, coordinateX, coordinateY)coordinateY += rowOffset 4. Complete VB.NET Source Code Implementation

'Header e.Graphics.DrawString("ABC Electronics", largeFont, Brushes.Black, leftMargin, yPos) yPos += 30 e.Graphics.DrawString("Invoice #: " & lblInvoiceNo.Text, font, Brushes.Black, leftMargin, yPos) yPos += 20 e.Graphics.DrawString("Date: " & DateTime.Now.ToShortDateString(), font, Brushes.Black, leftMargin, yPos) yPos += 30 e.Graphics.DrawString("Items:", font, Brushes.Black, leftMargin, yPos) yPos += 20

' Insert Invoice Dim invoiceQuery As String = "INSERT INTO Invoices (InvoiceNumber, CustomerID, InvoiceDate, SubTotal, GSTAmount, TotalAmount, PaymentMethod, Status) VALUES (@InvoiceNo, @CustomerID, @Date, @SubTotal, @GST, @Total, @PaymentMethod, 'Completed') SELECT SCOPE_IDENTITY()"

: txtInvoiceNo , txtCustomer , txtProductCode , txtProductName , txtUnitPrice , txtQuantity .

Buttons for "Save & Print", "Clear Form", and "Cancel Invoice". 4. Complete VB.NET Source Code Implementation