Vbnet+billing+software+source+code | AUTHENTIC |

If dt.Rows.Count > 0 Then Dim productID As Integer = dt.Rows(0)("ProductID") Dim pName As String = dt.Rows(0)("ProductName") Dim price As Decimal = Convert.ToDecimal(dt.Rows(0)("UnitPrice")) Dim gstPercent As Integer = Convert.ToInt32(dt.Rows(0)("GST_Percent"))

Private Sub txtProductCode_KeyDown(sender As Object, e As KeyEventArgs) Handles txtProductCode.KeyDown If e.KeyCode = Keys.Enter Then Dim productCode As String = txtProductCode.Text.Trim() Dim query As String = $"SELECT ProductID, ProductName, UnitPrice, StockQuantity, GST_Percent FROM tbl_Products WHERE ProductCode='productCode'" Dim dt As DataTable = ExecuteQuery(query) vbnet+billing+software+source+code

Public Function ExecuteQuery(ByVal query As String) As DataTable dt = New DataTable() Try OpenConnection() da = New SqlDataAdapter(query, conn) da.Fill(dt) Catch ex As Exception MessageBox.Show("Error: " & ex.Message) Finally CloseConnection() End Try Return dt End Function If dt.Rows.Count &gt

Public Sub CloseConnection() If conn.State = ConnectionState.Open Then conn.Close() End If End Sub Total) VALUES ('invoiceNo'

Dim detailQuery As String = $"INSERT INTO tbl_InvoiceDetails (InvoiceNo, ProductID, Quantity, Price, GST_Amount, Total) VALUES ('invoiceNo', productID, qty, price, gstAmt, total)" ExecuteNonQuery(detailQuery)

Introduction In the world of small to medium-sized retail businesses, supermarkets, and restaurants, billing software is the backbone of daily operations. While cloud-based solutions are popular, desktop applications built with VB.NET and SQL Server (or MS Access) remain highly relevant due to their speed, offline accessibility, and low cost of ownership.

Public Sub ExecuteNonQuery(ByVal query As String) Try OpenConnection() cmd = New SqlCommand(query, conn) cmd.ExecuteNonQuery() Catch ex As Exception MessageBox.Show("Error: " & ex.Message) Finally CloseConnection() End Try End Sub End Module Secure authentication using salt-hash (simplified here for demo).