Encode QR Code data message using C#

Tutorial for QR Code barcode generation in C#

Generate 2d barcode QR Code images in Visual C# .NET with complete sample C# source code

ON THIS PAGE:

Overview
Introduction
QR Code Basic Characteristics
- Encode character set & Data Mode in C#
- Maximum data length
Advanced Data Encoding

In this C# tutorial page, you will learn how to create QR Code with valid data encoding in ASP.NET, WinForms, WPF applications using C#.NET.

QR Code data encode with right data mode
GS1 QR Code data message encode
Besides Kanji (Japanese) characters, QR Code also supports international characters, such as Thai, Chinese chars
QR Code special characters encoding
Support .NET 7, 6, 5, .NET Core 3.1, 2.1 and .NET Framework 4.x, 3.x, 2.x
Word with C#, Visual Basic .NET, ASP.NET Core, MVC, Web Services, Console & Windows Applications.

How to create QR Code barcodes in ASP.NET MVC and Desktop application using C#

Download .NET QR Code Barcode Generator Suite
Install C# library to generate QR Code images in .NET apps
Step by Step Tutorial

C# QR Code Generator Introduction

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QR Code, also known as Denso Barcode, QRCode, Quick Response Code, is a kind of 2D (two dimensional) barcode widely used today.

C# QR Code barcode is .NET barcode generating SDK, which is a user-friendly, light weight barcode component for making QR Code barcodes in C#.NET Winforms application, C#.NET ASP.NET Web forms applications, C#.NET class and console applications. This document provides 100% C# source code to explain how to encode QR Code valid data with .NET Barcode suite using C# class.

OnBarcode C# Barcode Generator is designed to generate, create QR Code and other linear & 2d barcodes in Microsoft Word. Here are some more tutorials for C# QR Code generation concerning size & image setting.

QR Code Barcode Basic Characteristics

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Encode QR Code Valid Character in C#.NET

QR Code valid character set:

Numeric data. Quick to encode digits.
Alphanumeric data. Encode digits and letters only.
Byte characters. Perfect method to encode special characters, such as Unicode
Kanji characters. For Japanese characters only.

Encode Alphanumeric Character into QR Code Using C#.NET class

It allows encoding alphanumeric data, including digits 0 - 9; upper case letters A -Z; and nine other characters: space, $ % * + - . / : .

QRCode barcode = new QRCode();

barcode.Data = "OnBarcode";

barcode.DataMode = QRCodeDataMode.Alphanumeic;

barcode.Format = ImageFormat.Png;

barcode.drawBarcode("c:/qrcode.png");

Encode Numeric into QR Code Using C#.NET class

It allows encoding numeric data (digits 0 - 9).

QRCode barcode = new QRCode();

barcode.Data = "123456789";

barcode.DataMode = QRCodeDataMode.Numeric;

barcode.Format = ImageFormat.Png;

barcode.drawBarcode("c:/qrcode.png");

Encode Byte Characters into QR Code Using C#.NET class

It allows encoding byte data (default: ISO/IEC 8859-1).

QRCode barcode = new QRCode();

barcode.Data = "$ % * + - . / ";

barcode.DataMode = QRCodeDataMode.Byte;

barcode.Format = ImageFormat.Png;

barcode.drawBarcode("c:/qrcode.png");

Encode Kanji Characters into QR Code Using C#.NET class

It allows encoding Kanji characters. Please see SJIS (Shift JIS encoding): from ~9ddddd (Shift JIS 0x8140 ~ 0x9FFC and 0xE040 ~ 0xEBBF)

QRCode barcode = new QRCode();

barcode.Data = "~937727";

barcode.ProcessTild = True;

barcode.DataMode = QRCodeDataMode.Kanji;

barcode.Format = ImageFormat.Png;

barcode.drawBarcode("c:/qrcode.png");

Modify QR Code Valid Length in C#.NET

QR Code is variable-length 2-dimensional barcodes, the storage capacity see the table below:

Data Type	Maximum Data Storage Capacity
Alphanumeric Data	4,296 characters
Numeric Data	7,089 characters
Byte Character	2,953 characters
Kanji Character	1,817 characters

The length of QR Code is determined by the length of encoding data, for example:

barcode.Data = "1"; // in 1-digit length

barcode.Data = "123456789"; // in 9-digit length

barcode.Data = "12345678901234567890"; // in 20-digit length

QR Code maximum data length

Maximum data characters per QR Code symbol with Version 40-L

numeric data: 7,089 characters
alphanumeric data: 4,296 characters
byte data: 2,953 characters
Kanji data: 1,817 characters

Generate GS1 QR Code barcode images using C#

The foundational GS1 standard that defines how identification keys, data attributes and barcodes must be used in business applications.

GS1 QR Code barcode is a standalone, two-dimensional matrix symbology that is made up of square modules arranged in an overall square pattern, including a unique finder pattern located at three corners of the symbol.

QR Code is the only member of the QR Code family that supports GS1 system data structures, including Function 1 Symbol Character. ISO/IEC QR Code also contains specifications for Micro QR Code, but this symbology is not supported for the GS1 system. QR Code uses Reed-Solomon error correction (four selectable levels of error correction are specified), and this feature helps correct for partially damaged symbols.

GS1 QR Code symbols are read by two-dimensional imaging scanners or vision systems. Most other scanners that are not two-dimensional imagers cannot read GS1 QR Code. GS1 QR Code symbols are restricted for use with applications that will involve imaging scanners throughout the supply chain.

In QR Code generator C# library, there are two key properties to create GS1 QR Code.

FNC1: Value should be "FNC1.FNC1_1ST_POS"
Data: GS1 data should be pair of Application Identifier code (AI code) and data message (AI data), and AI code should be surrounded by parentheses. For example: GS1 data message "(17)050101(10)ABC123"

Sample C# source code to encode GS1 QR Code barcode

            QRCode barcode = new QRCode();

            //  It could encode GS1 element(s) by inserting a FNC1 symbol before all data characters.
            //  Each element contains a GS1 prefix (in parentheses) and fixed (or variable) length data content.
            //  Set FNC1 to FNC1.FNC1_1ST_POS to enable this feature.
            barcode.Data = "(17)050101(10)ABC123";
            barcode.FNC1 = FNC1.FNC1_1ST_POS;

            barcode.DataMode = QRCodeDataMode.Auto;

            //  Selecte format mode
            barcode.Version = QRCodeVersion.V3;

            // Barcode Size Related Settings
            barcode.UOM = UnitOfMeasure.PIXEL;
            barcode.X = 5;
            barcode.LeftMargin = 50;
            barcode.RightMargin = 50;
            barcode.TopMargin = 50;
            barcode.BottomMargin = 50;
            barcode.Resolution = 96;

            // Image format setting
            barcode.ImageFormat = System.Drawing.Imaging.ImageFormat.Png;

            barcode.drawBarcode("C://Projects//Test-Output//OnBarcode.com//csharp-qrcode-mode-gs1.png");

How to generate QR Code with International text using C#?

QR Code barcode does not support international text by default. If you need encode Arabic, Greek, Thai text. There are two solutions for you.

Convert internation text to byte array using UTF-8 encode, and generate QR Code using byte mode

Key property settings to encode international characters in QR Code C# barcode generator library:

ProcessTilde : Set value to true, to enable '~' in data message.

DataMode: It should be QRCodeDataMode.Byte

Data: The non-English text should be converted to byte array using UTF8 encoding.

Sample C# source code to encode Thai Text in QR Code barcode

            QRCode barcode = new QRCode();

            //  It may encode any Unicode characters after converting them to bytes in UTF-8 encode.
            //  And then, use Byte encodation to encode these byte data.
            String message = "สวัสดี";
            byte[] bytes = Encoding.UTF8.GetBytes(message);
            StringBuilder sb = new StringBuilder();
            foreach (byte b in bytes)
                sb.Append("~" + b.ToString().PadLeft(3, '0'));
            barcode.Data = sb.ToString();
            barcode.ProcessTilde = true;

            barcode.DataMode = QRCodeDataMode.Byte;

            //  Selecte format mode
            barcode.Version = QRCodeVersion.V3;

            // Barcode Size Related Settings
            barcode.UOM = UnitOfMeasure.PIXEL;
            barcode.X = 5;
            barcode.LeftMargin = 50;
            barcode.RightMargin = 50;
            barcode.TopMargin = 50;
            barcode.BottomMargin = 50;
            barcode.Resolution = 96;

            // Image format setting
            barcode.ImageFormat = System.Drawing.Imaging.ImageFormat.Png;

            barcode.drawBarcode("C://Projects//Test-Output//OnBarcode.com//csharp-qrcode-mode-thai.png");

How to create QR Code barcode with non-printable chars (such as '[CR]' (Carriage Return)) using C#?

To encode QR Code with non-printable or non-visible chars, such as '[CR]' (Carriage Return), you need generate QR Code with byte data mode (QRCodeDataMode.Auto or QRCodeDataMode.Byte). Here are the sample property settings

ProcessTilde : Set value to true, to enable '~' in data message.

DataMode: It should be QRCodeDataMode.Auto or QRCodeDataMode.Byte

Data: The non printable character should be converted to three digits (in ASCII value), such as '~013'.

Sample C# source code to encode non printable chars '[CR]' (Carriage Return) in QR Code

            QRCode barcode = new QRCode();

            //  It could encode non-printable chars by converting char ascii value to THREE digits, in format "~ddd",
            //  Set ProcessTilde to true to enable this feature.
            barcode.Data = "~013"; // char '[CR]' or carriage return   
            barcode.ProcessTilde = true;

            barcode.DataMode = QRCodeDataMode.Auto;

            //  Selecte format mode
            barcode.Version = QRCodeVersion.V3;

            // Barcode Size Related Settings
            barcode.UOM = UnitOfMeasure.PIXEL;
            barcode.X = 5;
            barcode.LeftMargin = 50;
            barcode.RightMargin = 50;
            barcode.TopMargin = 50;
            barcode.BottomMargin = 50;
            barcode.Resolution = 96;

            // Image format setting
            barcode.ImageFormat = System.Drawing.Imaging.ImageFormat.Png;

            barcode.drawBarcode("W://Projects//Test-Output//OnBarcode.com//csharp-qrcode-mode-non-print.png");