Vb.net Billing Software Source Code May 2026

The development of billing software using Visual Basic .NET (VB.NET) represents a practical application of the .NET framework to solve critical business administrative needs. At its core, billing software serves as a bridge between service delivery and revenue collection, automating the generation of invoices and the tracking of financial transactions. Architectural Overview

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 Private Sub cmbProductName_SelectedIndexChanged(sender As Object, e As EventArgs) Handles cmbProductName.SelectedIndexChanged If cmbProductName.SelectedValue IsNot Nothing Then Try Dim productID As Integer = Convert.ToInt32(cmbProductName.SelectedValue) Dim query As String = "SELECT ProductCode, UnitPrice, GSTPercentage FROM Products WHERE ProductID = @ProductID" DBConnection.OpenConnection() Using cmd As New SqlCommand(query, DBConnection.conn) cmd.Parameters.AddWithValue("@ProductID", productID) Using reader As SqlDataReader = cmd.ExecuteReader() If reader.Read() Then txtProductCode.Text = reader("ProductCode").ToString() txtPrice.Text = reader("UnitPrice").ToString() txtGST.Text = reader("GSTPercentage").ToString() txtQuantity.Text = "1" CalculateTotal() End If End Using End Using DBConnection.CloseConnection() Catch ex As Exception MessageBox.Show("Error: " & ex.Message) End Try End If End Sub

Table: Products (ProductID, ProductName, UnitPrice, StockQuantity) vb.net billing software source code