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Open Source QRCode Library

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4.92 (142 votes)
20 Sep 2007CPOL
How to use QRCode library to encode and decode QRCode
Screenshot - qrcode_app_decode.jpg

Introduction

In this article, I will briefly describe the functionalities of the QRCode library.

Background

QRCode library is a .NET component that can be used to encode and decode QRCode. QRCode is a 2 dimensional bar code that originated in Japan. Nowadays, it is widely used in a wide range of industries, e.g. for vehicle parts tracking and inventory management.

QR stands for "Quick Response". It was created by the Japanese corporation Denso-Wave in 1994 and is aimed at decoding contents at high speed. Nowadays, QR Code is used in mobile phones to ease data entry.

QRCode can also be printed on a business card or shown on any display, which can then be captured by the mobile phone provided the mobile phone has the software to read QRCode.

QRCode library provides functions to:

  1. Encode content into a QR Code image which can be saved in JPEG, GIF, PNG, or Bitmap formats
  2. Decode a QR Code image

Using the Code

The library can be used in any .NET 2.0 Windows Application, ASP.NET Web application or Windows Mobile device application.

Some sample screenshots are displayed below:

Screenshot - qrcode_app_encode.jpg

Screenshot - qrcode_mobile_encode.jpg

QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
          String encoding = cboEncoding.Text ;
          if (encoding == "Byte") {
              qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;
          } else if (encoding == "AlphaNumeric") {
              qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.ALPHA_NUMERIC;
          } else if (encoding == "Numeric") {
              qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.NUMERIC;
          }
          try {
              int scale = Convert.ToInt16(txtSize.Text);
              qrCodeEncoder.QRCodeScale = scale;
          } catch (Exception ex) {
              MessageBox.Show("Invalid size!");
              return;
          }
          try {
              int version = Convert.ToInt16(cboVersion.Text) ;
              qrCodeEncoder.QRCodeVersion = version;
          } catch (Exception ex) {
              MessageBox.Show("Invalid version !");
          }

          string errorCorrect = cboCorrectionLevel.Text;
          if (errorCorrect == "L")
              qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.L;
          else if (errorCorrect == "M")
              qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;
          else if (errorCorrect == "Q")
              qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.Q;
          else if (errorCorrect == "H")
              qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.H;

          Image image;
          String data = txtEncodeData.Text;
          image = qrCodeEncoder.Encode(data);
          picEncode.Image = image;

History

  • 20th September, 2007: Initial post

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

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About the Author

mengwangk
Software Developer (Senior)
Malaysia Malaysia
A programmer for a long time, and still learning everyday.

A supporter for open source solutions, and have written quite a few open source software both in .NET and Java.

https://mengwangk.github.io/

Comments and Discussions

 
QuestionVote 0 Pin
Protection&Safe19-Nov-13 7:13
MemberProtection&Safe19-Nov-13 7:13 
AnswerRe: Vote 0 Pin
Yves17-Jan-18 6:17
MemberYves17-Jan-18 6:17 
QuestionHow to generate vCard. Its possible by messagingToolkit. Pin
ajitkmr0923-Oct-13 2:06
Memberajitkmr0923-Oct-13 2:06 
Answer[SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Philippe9122-Oct-13 5:02
MemberPhilippe9122-Oct-13 5:02 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
muharrem2-Dec-13 23:34
Membermuharrem2-Dec-13 23:34 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Philippe916-Mar-14 0:28
MemberPhilippe916-Mar-14 0:28 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Nishant Betawar2-Feb-14 5:11
MemberNishant Betawar2-Feb-14 5:11 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Philippe916-Mar-14 0:19
MemberPhilippe916-Mar-14 0:19 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Shaitan-Babay5-Mar-14 23:17
MemberShaitan-Babay5-Mar-14 23:17 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Philippe916-Mar-14 0:18
MemberPhilippe916-Mar-14 0:18 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Shaitan-Babay6-Mar-14 0:39
MemberShaitan-Babay6-Mar-14 0:39 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
ronaldfer11-Mar-14 7:07
Memberronaldfer11-Mar-14 7:07 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Nandoviski9-Apr-14 11:33
MemberNandoviski9-Apr-14 11:33 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Khayralla8-May-14 9:46
MemberKhayralla8-May-14 9:46 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Sharma61923-May-14 20:23
MemberSharma61923-May-14 20:23 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
yasielsegui19-Aug-14 9:36
Memberyasielsegui19-Aug-14 9:36 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Ash20131-Oct-14 14:58
MemberAsh20131-Oct-14 14:58 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Philippe912-Oct-14 4:00
MemberPhilippe912-Oct-14 4:00 
GeneralRe: [SOLVED] Is this library easily modifiable to work with accented chars? Yes, it is... Pin
Ash20137-Oct-14 12:15
MemberAsh20137-Oct-14 12:15 
GeneralMy vote of 1 Pin
Kangerm00se7-Aug-13 4:52
MemberKangerm00se7-Aug-13 4:52 
GeneralVote of 3 Pin
Daniel_865-Aug-13 21:09
MemberDaniel_865-Aug-13 21:09 
QuestionThe famous indexoutofrange exception on line 654 Pin
dada20103-Jul-13 23:13
Memberdada20103-Jul-13 23:13 
Suggestioni hope , have help manual Pin
cheng11011018-Jun-13 1:22
Membercheng11011018-Jun-13 1:22 
Questionhow to create qr code automatically send sms Pin
Dư Bùi11-Jun-13 0:44
MemberDư Bùi11-Jun-13 0:44 
GeneralMy vote of 5 Pin
Member 97166372-Jun-13 23:57
MemberMember 97166372-Jun-13 23:57 

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Article
Posted 20 Sep 2007

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