How to Build a Production-Ready Invoice Builder in .NET Using IronPDF
Source: Dev.to
Invoice Builder requirements
Business requirements
- Create Invoice Customers and Senders
- Create Invoices: invoice & date details, existing Customer and Sender data, line items
- Generate and download Invoice PDF files
PDF requirements
- Consistent layout at any length: a single item or hundreds of rows should paginate cleanly.
- Accurate rendering and stable formatting on any device.
- High‑quality rendering with crisp text, logos, and tables suitable for printing or archiving.
- PDF/UA compliance for long‑term storage and audit needs.
- Digital signatures to prove integrity and origin, with an optional visible signature appearance.
- Fully managed, cross‑platform runtime with fast generation and small operational overhead.
UI Features
Home Screen
- Tabs: Invoices, Customers, Senders
Invoices
- List paged invoices in a table view
- Create new invoices
- Table actions: View, Edit, Delete (with confirmation), Download PDF
Customers
- List paged customers in a table view
- Create new customers
- Table actions: View, Edit, Delete (with confirmation)
Senders
- List paged senders in a table view
- Create new senders
- Table actions: View, Edit, Delete (with confirmation)
Implementation Tech Stack
Backend
- ASP.NET Core 10, EF Core, IronPDF for generating PDFs
Frontend
- React, TypeScript, TailwindCSS
Architecture
- Modular Monolith
- Vertical Slice Architecture + Clean Architecture
Database
- PostgreSQL
Deployment
- Docker Compose
Invoice Builder UI Overview
Home Screen
The Invoices tab shows a list of invoices with actions such as View, Edit, Delete, and Download PDF. To create a new invoice, a Customer and a Sender must exist first.
Create Customer / Sender
Create Invoice Form
Fields to fill
- Invoice Details (Number, Dates, Tax Rate, Notes, etc.)
- Sender Info
- Customer Info
- Line Items
Select a Customer and Sender from dropdowns.
After clicking Create Invoice, the invoice is stored in the database. The PDF can be downloaded from the invoice details page or the Invoices list.
Selecting a C# PDF Library for Invoice Generation
There are several options for generating PDFs in C# and ASP.NET Core:
- IronPDF
- QuestPDF
- Aspose.PDF
- PuppeteerSharp
IronPDF
IronPDF is a powerful .NET library for creating, editing, signing, and rendering PDFs. It offers a developer‑friendly, fluent API.
Pros
- HTML, DOCX, RTF, XML, MD, Image to PDF conversion
- PDF from URL, PDF to HTML
- Compliance with PDF/A, PDF/UA, and PDF/X standards
- Fully managed and cross‑platform
- High‑performance rendering
- Digital signatures & security
- Rich PDF manipulation (edit, merge, split)
- Good documentation
Cons
- Requires a paid license for commercial use.
QuestPDF
QuestPDF is an open‑source PDF generation library that uses a fluent C# API to build documents directly in code.
Pros
- Fluent C# API with layout‑based approach
- Consistent, repeatable output for structured documents
- Good documentation with many examples
- Free for commercial use for small companies
Cons
- No HTML‑to‑PDF conversion
- No built‑in support for PDF/A or PDF/UA compliance
- Lacks digital signatures, security features, interactive forms, or JavaScript rendering
- Larger companies need a paid license for commercial use
Aspose.PDF
Aspose.PDF provides advanced capabilities for programmatic PDF creation and manipulation.
Pros
- Extensive control over PDF elements (paragraphs, tables, images, forms, annotations)
- Advanced manipulation features for complex workflows
- Support for PDF/A standards and digital signatures
- Mature library with a long enterprise track record
Cons
- Verbose API; even simple tasks require detailed code, leading to a steeper learning curve
- Limited HTML‑to‑PDF conversion; lacks a native Chromium engine, resulting in rendering limitations
PuppeteerSharp
Note: Not detailed in the original content; included here for completeness.
By evaluating the pros and cons, IronPDF emerges as a strong candidate for a production‑ready invoice builder that requires HTML‑to‑PDF conversion, compliance standards, and digital signing capabilities.