How to Generate QR Code in C# Windows Applications

1. Create a Windows Forms Application in Microsoft Visual Studio

Open Visual Studio > Click on Create New Project > Select Windows Forms Application Template > Press Next > Name the Project > Press Next > Select your Target .NET Framework > Click the Create button.

After creating the project, design the form using the following controls from the Visual Studio toolbox: PictureBox, Label, TextBox, and Button.

A Windows Forms Application UI to load an image and generate a QR Code

2. Install the QR Code Generator .NET Library in C#

Install-Package BarCode

3. Importing NameSpaces

For this tutorial, to ensure adequate references, the IronBarCode namespace along with other system assemblies is necessary.

using IronBarCode; // Provides functionality for QR and barcode generation
using System; // Contains fundamental classes and base classes that define commonly-used value and reference data types
using System.Drawing; // Provides access to GDI+ basic graphic functionality
using System.Linq; // Provides classes and interfaces that support queries

using IronBarCode; // Provides functionality for QR and barcode generation
using System; // Contains fundamental classes and base classes that define commonly-used value and reference data types
using System.Drawing; // Provides access to GDI+ basic graphic functionality
using System.Linq; // Provides classes and interfaces that support queries

4. Create a QR Code with 1 Line of Code

The following sample code allows you to generate a QR code image with just one line of code. Enter the desired text into the text box for which you want to generate a QR code. Place this code in the "Generate PNG" button click event. The QR code images can be saved in PNG format.

// Simple QR Code generation
private void button1_Click(object sender, EventArgs e)
{
    // Generate a QR code from the text provided in the TextBox
    GeneratedBarcode qrCode = QRCodeWriter.CreateQrCode(textBox1.Text);

    // Save the generated QR code as a PNG file
    qrCode.SaveAsPng("QrCode.png");
}

// Simple QR Code generation
private void button1_Click(object sender, EventArgs e)
{
    // Generate a QR code from the text provided in the TextBox
    GeneratedBarcode qrCode = QRCodeWriter.CreateQrCode(textBox1.Text);

    // Save the generated QR code as a PNG file
    qrCode.SaveAsPng("QrCode.png");
}

Here is the output of the QR code generator:

QR code of: https://ironsoftware.com/csharp/barcode/docs/

5. Adding a Logo to a QR Code Image

By using the CreateQrCodeWithLogo method from the QRCodeWriter class, additional information, such as a logo, can be added to the QR code. The sample code illustrates how easy this is.

Browse the logo from your computer, and it will open in PictureBox. The code goes as follows:

// Open file dialog to select an image
OpenFileDialog open = new OpenFileDialog();
// Set image file filters to ensure valid image types are opened
open.Filter = "Image Files(*.jpg; *.png; *.jpeg; *.gif; *.bmp)|*.jpg; *.png; *.jpeg; *.gif; *.bmp";
if (open.ShowDialog() == DialogResult.OK) {
    // Display image in PictureBox and store file path for later use
    pictureBox1.Image = new Bitmap(open.FileName);
    // Store image file path in class data member
    ImageFileName = open.FileName;
}

// Open file dialog to select an image
OpenFileDialog open = new OpenFileDialog();
// Set image file filters to ensure valid image types are opened
open.Filter = "Image Files(*.jpg; *.png; *.jpeg; *.gif; *.bmp)|*.jpg; *.png; *.jpeg; *.gif; *.bmp";
if (open.ShowDialog() == DialogResult.OK) {
    // Display image in PictureBox and store file path for later use
    pictureBox1.Image = new Bitmap(open.FileName);
    // Store image file path in class data member
    ImageFileName = open.FileName;
}

Next, simply type the text in the text box, place this code in the Generate PNG button, and click.

// Generate a QR code with a logo
GeneratedBarcode qrCode = QRCodeWriter.CreateQrCodeWithLogo(textBox1.Text, ImageFileName, 500);
// Save the generated QR code with logo as a PNG file
qrCode.SaveAsPng("QrCodeWithImage.png");

// Generate a QR code with a logo
GeneratedBarcode qrCode = QRCodeWriter.CreateQrCodeWithLogo(textBox1.Text, ImageFileName, 500);
// Save the generated QR code with logo as a PNG file
qrCode.SaveAsPng("QrCodeWithImage.png");

This code adds the Iron logo to the barcode. It automatically sizes it to an appropriate size where the pure code is still readable and aligns that logo to the QR code square grid so that it looks appropriate.

C# Create QR Code With Logo Image

6. Save as a PDF or HTML Image

Finally, the generated QR code can be saved as a PDF or HTML image. The final line of code opens the PDF in your default PDF browser for your convenience. Add the SaveAsPdf in the Generate PDF button and SaveAsHtmlFile in the Generate HTML button.

// Generate a QR code with a logo
GeneratedBarcode qrCode = QRCodeWriter.CreateQrCodeWithLogo(textBox1.Text, ImageFileName, 500);

// Save the QR code as a PDF file
qrCode.SaveAsPdf("QRWithLogo.pdf");

// Also, save the QR code as an HTML file
qrCode.SaveAsHtmlFile("QRWithLogo.html");

// Generate a QR code with a logo
GeneratedBarcode qrCode = QRCodeWriter.CreateQrCodeWithLogo(textBox1.Text, ImageFileName, 500);

// Save the QR code as a PDF file
qrCode.SaveAsPdf("QRWithLogo.pdf");

// Also, save the QR code as an HTML file
qrCode.SaveAsHtmlFile("QRWithLogo.html");