Building a Complete VB.NET Billing Software: Architecture, Source Code, and Implementation
Place this code directly behind your primary user interface form.
Easy to maintain and deploy on any Windows environment. Conclusion vb.net billing software source code
Private Function ValidateFields() As Boolean If String.IsNullOrWhiteSpace(txtProductCode.Text) Then MessageBox.Show("Product code is required") Return False End If If String.IsNullOrWhiteSpace(txtProductName.Text) Then MessageBox.Show("Product name is required") Return False End If If Not Decimal.TryParse(txtPrice.Text, Nothing) Then MessageBox.Show("Invalid price") Return False End If Return True End Function
Public Class frmBilling Private dtCart As New DataTable() Private currentInvoiceNumber As String = "" Building a Complete VB
Add the required user interface controls onto the designer window ( txtCustomerName , cboProducts , dgvInvoiceItems , txtSubTotal , etc.), ensuring the names match the event handlers in the source code.
If you would like to expand this system further,g., generating daily or monthly sales reports) If you would like to expand this system further,g
CREATE TABLE Customers ( CustomerID INT IDENTITY(1,1) PRIMARY KEY, CustomerName VARCHAR(100) NOT NULL, Phone VARCHAR(20), TotalBalance DECIMAL(18,2) DEFAULT 0.00 ); CREATE TABLE Products ( ProductID INT IDENTITY(1,1) PRIMARY KEY, ProductName VARCHAR(100) NOT NULL, Price DECIMAL(18,2) NOT NULL, StockQuantity INT NOT NULL ); CREATE TABLE Invoices ( InvoiceNo INT IDENTITY(1001,1) PRIMARY KEY, InvoiceDate DATETIME DEFAULT GETDATE(), CustomerID INT FOREIGN KEY REFERENCES Customers(CustomerID), GrossAmount DECIMAL(18,2), TaxAmount DECIMAL(18,2), NetAmount DECIMAL(18,2) ); CREATE TABLE InvoiceDetails ( ID INT IDENTITY(1,1) PRIMARY KEY, InvoiceNo INT FOREIGN KEY REFERENCES Invoices(InvoiceNo), ProductID INT FOREIGN KEY REFERENCES Products(ProductID), Quantity INT NOT NULL, UnitPrice DECIMAL(18,2) NOT NULL, TotalPrice DECIMAL(18,2) NOT NULL ); Use code with caution. 2. Database Connection Wrapper Module
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