public static string GetHTMLString(int id) { decimal total = 0; LeasingContext _context = new LeasingContext(); var products = _context.Products.ToList(); var leasing = _context.Leasings.Where(ld => ld.LeasingId == id) .Include(l => l.LeasingDetails) .ThenInclude(l => l.Product) .ToList(); var sb = new StringBuilder(); sb.AppendFormat(@" <html> <head> </head> <body> <div class='header'><h1>Order no. {0} </h1></div> <table align='center'> <tr> <th>Product Name</th> <th>Product Price</th> <th>Product Code</th> <th>Amount</th> <th>Total</th> </tr>", id); foreach (var ld in leasing) { foreach (var l in ld.LeasingDetails) { sb.AppendFormat(@"<tr> <td>{0}</td> <td>{1}</td> <td>{2}</td> <td>{3}</td> <td>{4}</td> </tr>", l.Product.ProductName, l.Product.ProductPrice, l.Product.ProductCode, l.LeasingDetailAmount, l.LeasingDetailAmount * l.Product.ProductPrice); total += l.LeasingDetailAmount * l.Product.ProductPrice; } } sb.AppendFormat(@"<tr><td colspan='4'></td><td></td>{0}</tr> </table> </body> </html>", total); return(sb.ToString()); }