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
This snippet demonstrates calculating the total based on quantity and unit price.
' 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
This article explores the essential components, structure, and benefits of accessing , offering insights for both beginners and experienced developers. Why Choose VB.NET for Billing Software? vb.net billing software source code
Minimal VB.NET code patterns (pseudo-concrete)
Every time a transaction completes successfully, an optimized update query reduces the StockQuantity column inside the Products table. This prevents double selling out-of-stock items, keeping real-time inventory accurate. Advanced Architecture Upgrades
Handling multiple payment methods (Cash, Credit Card, Bank Transfer) and tracking outstanding balances. Why Choose VB
: Computes subtotals, tax rates, and discounts instantly on the front end.
This layer contains the calculations and validation rules (e.g., checking if stock exists before adding it to an invoice). 4. The Presentation Layer (Windows Forms)
Built-in tools like Crystal Reports or Microsoft Report Viewer make generating invoices straightforward. and Total .
A DataGridView named dgvInvoice with 5 columns: ProdID , Product Name , Price , Qty , and Total . Billing Summary Panel: TextBox named txtSubTotal (Read-only). TextBox named txtTax (Default text: 10 for 10%). TextBox named txtDiscount (Default text: 0 ). TextBox named txtGrandTotal (Read-only).
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