' Assume GST is stored per product Dim gstPercent As Decimal = Convert.ToDecimal(row.Cells("GSTPercent").Value) Dim lineAmount As Decimal = Convert.ToDecimal(row.Cells("Amount").Value) totalTax += (lineAmount * gstPercent / 100) Next
Start with a clean database schema, implement the core billing loop, and then incrementally add features like printing, barcodes, and customer history. With the code examples provided above, you can build a production-ready billing system in weeks, not months. vb.net billing software source code
Imports System.Data.SqlClient Module modDatabase Public conn As SqlConnection Public cmd As SqlCommand Public da As SqlDataAdapter Public dt As DataTable ' Assume GST is stored per product Dim