VB.NET remains a powerful tool for rapid application development (RAD), especially for small business tools. By combining a clean UI with a structured SQL backend, you can create a reliable billing system tailored to specific needs.
Imports System.Data.SqlClient Public Class dbConfig Public conn As New SqlConnection("Data Source=YOUR_SERVER;Initial Catalog=BillingDB;Integrated Security=True") Public Sub OpenConnection() If conn.State = ConnectionState.Closed Then conn.Open() End Sub Public Sub CloseConnection() If conn.State = ConnectionState.Open Then conn.Close() End Sub End Class Use code with caution. 4. Designing the Billing UI Your main form ( frmBilling.vb ) should include: Product ID, Quantity, Price, Customer Name. DataGridView: To display the current items in the cart. Buttons: "Add to Cart", "Generate Invoice", "Clear". 5. Core Logic: Adding Items to Grid vb.net billing software source code
Private Sub btnAddToCart_Click(sender As Object, e As EventArgs) Handles btnAddToCart.Click Dim total As Decimal = CDec(txtPrice.Text) * CInt(txtQty.Text) ' Add row to DataGridView dgvItems.Rows.Add(txtProductID.Text, txtProductName.Text, txtPrice.Text, txtQty.Text, total) CalculateGrandTotal() End Sub Private Sub CalculateGrandTotal() Dim grandTotal As Decimal = 0 For Each row As DataGridViewRow In dgvItems.Rows grandTotal += CDec(row.Cells(4).Value) Next lblGrandTotal.Text = grandTotal.ToString("C") End Sub Use code with caution. 6. Saving the Invoice to the Database Buttons: "Add to Cart", "Generate Invoice", "Clear"
Once the user clicks "Generate Invoice," the data must be committed to the SQL database. Buttons: "Add to Cart"
This code snippet handles adding items to the DataGridView and calculating the subtotal.