C# || How To Generate, Create & Read A QR Code Using C#

May 13, 2021 admin No comments

The following is a module with functions which demonstrates how to generate, create and read a QR code using C#.

The functions demonstrated on this page has the ability to create and encode a string to a QR code byte array, and another function to read and decode a byte array QR code to a string.

The following functions use ZXing.Net to create and read QR codes.

Note: To use the functions in this module, make sure you have the ‘ZXing.Net‘ package installed in your project.

One way to do this is, in your Solution Explorer (where all the files are shown with your project), right click the ‘References‘ folder, click ‘Manage NuGet Packages….‘, then type ‘ZXing.Net‘ in the search box, and install the package titled ZXing.Net in the results Tab.

1. Create QR Code – Encode

The example below demonstrates the use of ‘Utils.QRCode.Create‘ to create a QR code byte array from string data.

The optional function parameters allows you to specify the QR code height, width and margin.





		
		
			1. Create QR Code - Encode
			
C#
			
			// Create QR Code - Encode

// Data to encode
var data = "https://www.programmingnotes.org/";

// Encode data to a QR code byte array
var qrBytes = Utils.QRCode.Create(data);

// Display bytes length
Console.WriteLine($"Length: {qrBytes.Length}");

// expected output:
/*
    Length: 1959
*/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
				
						// Create QR Code - Encode
 
// Data to encode
var data = "https://www.programmingnotes.org/";
 
// Encode data to a QR code byte array
var qrBytes = Utils.QRCode.Create(data);
 
// Display bytes length
Console.WriteLine($"Length: {qrBytes.Length}");
 
// expected output:
/*
    Length: 1959
*/

2. Read QR Code – Decode

The example below demonstrates the use of ‘Utils.QRCode.Read‘ to read a QR code byte array and decode its contents to a string.





		
		
			2. Read QR Code - Decode
			
C#
			
			// Read QR Code - Decode

// Read QR as byte array
byte[] qrBytes;

// Decode QR code to a string
var data = Utils.QRCode.Read(qrBytes);

// ... Do something with the result string
			
				
					
				
					1
2
3
4
5
6
7
8
9
				
						// Read QR Code - Decode
 
// Read QR as byte array
byte[] qrBytes;
 
// Decode QR code to a string
var data = Utils.QRCode.Read(qrBytes);
 
// ... Do something with the result string

3. Utils Namespace

The following is the Utils Namespace. Include this in your project to start using!





		
		
			Utils Namespace
			
C#
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 13, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Utils.cs
//    Description: Handles general utility functions
// ============================================================================
using System;

namespace Utils {
    public static class QRCode { 
        /// <summary>
        /// Converts a string and encodes it to a QR code byte array
        /// </summary>
        /// <param name="data">The data to encode</param>
        /// <param name="height">The height of the QR code</param>
        /// <param name="width">The width of the QR code</param>
        /// <param name="margin">The margin around the QR code</param>
        /// <returns>The byte array of the data encoded into a QR code</returns>
        public static byte[] Create(string data, int height = 100
                        , int width = 100, int margin = 0) {
            byte[] bytes = null;
            var barcodeWriter = new ZXing.BarcodeWriter() {
                Format = ZXing.BarcodeFormat.QR_CODE,
                Options = new ZXing.QrCode.QrCodeEncodingOptions() {
                    Height = height, Width = width, Margin = margin
                }
            };
            using (var image = barcodeWriter.Write(data)) {
                using (var stream = new System.IO.MemoryStream()) {
                    image.Save(stream, System.Drawing.Imaging.ImageFormat.Png);
                    bytes = stream.ToArray();
                }
            }
            return bytes;
        }

        /// <summary>
        /// Converts a QR code and decodes it to its string data 
        /// </summary>
        /// <param name="bytes">The QR code byte array</param> 
        /// <returns>The string data decoded from the QR code</returns>
        public static string Read(byte[] bytes) {
            var result = string.Empty;
            using (var stream = new System.IO.MemoryStream(bytes)) {
                using (var image = System.Drawing.Image.FromStream(stream)) {
                    var barcodeReader = new ZXing.BarcodeReader() { 
                        AutoRotate = true, TryInverted = true,
                        Options = new ZXing.Common.DecodingOptions() { 
                            TryHarder = true,
                            PossibleFormats = new ZXing.BarcodeFormat[] {
                                ZXing.BarcodeFormat.QR_CODE
                            }
                        }
                    };
                    var decoded = barcodeReader.Decode((System.Drawing.Bitmap)image);
                    if (decoded != null) {
                        result = decoded.Text;
                    }
                }
            }
            return result;
        }
    }
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 13, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Utils.cs
//    Description: Handles general utility functions
// ============================================================================
using System;
 
namespace Utils {
    public static class QRCode { 
        /// <summary>
        /// Converts a string and encodes it to a QR code byte array
        /// </summary>
        /// <param name="data">The data to encode</param>
        /// <param name="height">The height of the QR code</param>
        /// <param name="width">The width of the QR code</param>
        /// <param name="margin">The margin around the QR code</param>
        /// <returns>The byte array of the data encoded into a QR code</returns>
        public static byte[] Create(string data, int height = 100
                        , int width = 100, int margin = 0) {
            byte[] bytes = null;
            var barcodeWriter = new ZXing.BarcodeWriter() {
                Format = ZXing.BarcodeFormat.QR_CODE,
                Options = new ZXing.QrCode.QrCodeEncodingOptions() {
                    Height = height, Width = width, Margin = margin
                }
            };
            using (var image = barcodeWriter.Write(data)) {
                using (var stream = new System.IO.MemoryStream()) {
                    image.Save(stream, System.Drawing.Imaging.ImageFormat.Png);
                    bytes = stream.ToArray();
                }
            }
            return bytes;
        }
 
        /// <summary>
        /// Converts a QR code and decodes it to its string data 
        /// </summary>
        /// <param name="bytes">The QR code byte array</param> 
        /// <returns>The string data decoded from the QR code</returns>
        public static string Read(byte[] bytes) {
            var result = string.Empty;
            using (var stream = new System.IO.MemoryStream(bytes)) {
                using (var image = System.Drawing.Image.FromStream(stream)) {
                    var barcodeReader = new ZXing.BarcodeReader() { 
                        AutoRotate = true, TryInverted = true,
                        Options = new ZXing.Common.DecodingOptions() { 
                            TryHarder = true,
                            PossibleFormats = new ZXing.BarcodeFormat[] {
                                ZXing.BarcodeFormat.QR_CODE
                            }
                        }
                    };
                    var decoded = barcodeReader.Decode((System.Drawing.Bitmap)image);
                    if (decoded != null) {
                        result = decoded.Text;
                    }
                }
            }
            return result;
        }
    }
}// http://programmingnotes.org/

4. More Examples

Below are more examples demonstrating the use of the ‘Utils‘ Namespace. Don’t forget to include the module when running the examples!





		
		
			More Examples
			
C#
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 13, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Program.cs
//    Description: The following demonstrates the use of the Utils Namespace
// ============================================================================
using System;
using System.Diagnostics;

public class Program {
    static void Main(string[] args) {
        try {
            // Data to encode
            var data = "https://www.programmingnotes.org/";

            // Encode data to a QR code byte array
            var bytes = Utils.QRCode.Create(data);

            Display($"Length: {bytes.Length}");

            // Decode QR code to a string
            var result = Utils.QRCode.Read(bytes);

            Display($"Result: {result}");
        } catch (Exception ex) {
            Display(ex.ToString());
        } finally {
            Console.ReadLine();
        }
    }

    static void Display(string message) {
        Console.WriteLine(message);
        Debug.Print(message);
    }
}// http://programmingnotes.org/
			
				
					
				
					1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
				
						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 13, 2021
//    Taken From: http://programmingnotes.org/
//    File:  Program.cs
//    Description: The following demonstrates the use of the Utils Namespace
// ============================================================================
using System;
using System.Diagnostics;
 
public class Program {
    static void Main(string[] args) {
        try {
            // Data to encode
            var data = "https://www.programmingnotes.org/";
 
            // Encode data to a QR code byte array
            var bytes = Utils.QRCode.Create(data);
 
            Display($"Length: {bytes.Length}");
 
            // Decode QR code to a string
            var result = Utils.QRCode.Read(bytes);
 
            Display($"Result: {result}");
        } catch (Exception ex) {
            Display(ex.ToString());
        } finally {
            Console.ReadLine();
        }
    }
 
    static void Display(string message) {
        Console.WriteLine(message);
        Debug.Print(message);
    }
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Was this article helpful?

👍 YesNo

Posted in: C#, Console Tags: c-sharp, qr code

C# || How To Generate, Create & Read A QR Code Using C#

Related

Leave a ReplyCancel reply

Search

Compile Your Code Now

Translate Page

Popular Pages

Recent

Archives

Categories