Comment implémenter facilement QRCoder dans ASP.NET Core à l'aide de C #

QRCoder est une bibliothèque d'implémentation de QR Code très populaire écrite en C #. Il est disponible dans GitHub . Ici, je vais implémenter la bibliothèque QRCoder pour générer des codes QR dans mon application ASP.NET Core. J'utiliserai également C #.

Je vais implémenter QRCoder de 3 manières, qui sont:

1. Créez une image Bitmap QR Code pour n'importe quel texte.

2. Créez un fichier de code QR (.qrr) pour n'importe quel texte, puis enregistrez ces fichiers dans l'application.

3. Lisez et affichez tous les fichiers de code QR (.qrr).

Commençons par l'installation de QRCoder dans ASP.NET Core Framework.

Vous pouvez télécharger le code complet depuis mon référentiel GitHub .

Installation

Installez QRCoder via NuGet Package Manager. Si vous souhaitez utiliser NuGet, recherchez simplement «QRCoder» ou exécutez la commande suivante dans la console NuGet Package Manager:

PM> Install-Package QRCoder

Le QRCoder s'installera dans 1 minute et sera prêt à être utilisé.

Commençons maintenant par l'implémentation de QRCoder des 3 manières mentionnées ci-dessus.

Créer une image bitmap QR Code pour n'importe quel texte

Créez un nouveau contrôleur appelé « QRCoderController» dans le dossier Contrôleurs. Le contrôleur sera créé et il ne contiendra qu'une seule méthode d'action appelée ' Index':

public IActionResult Index() { return View(); }

Importez les espaces de noms suivants dans le contrôleur:

using System; using System.Collections.Generic; using System.Drawing; using System.IO; using Microsoft.AspNetCore.Mvc; using QRCoder;

Ensuite, ajoutez l'action d'index de type [HttpPost]au contrôleur:

[HttpPost] public IActionResult Index(string qrText) { QRCodeGenerator qrGenerator = new QRCodeGenerator(); QRCodeData qrCodeData = qrGenerator.CreateQrCode(qrText, QRCodeGenerator.ECCLevel.Q); QRCode qrCode = new QRCode(qrCodeData); Bitmap qrCodeImage = qrCode.GetGraphic(20); return View(BitmapToBytes(qrCodeImage)); }
Cette action d'index reçoit un paramètre de chaîne appelé «qrText». Il contient le texte fourni par un contrôle d'entrée défini dans la vue. Ce texte sera converti en image bitmap QR Code. Les lignes de code suivantes font ce travail:
QRCodeGenerator qrGenerator = new QRCodeGenerator(); QRCodeData qrCodeData = qrGenerator.CreateQrCode(qrText, QRCodeGenerator.ECCLevel.Q); QRCode qrCode = new QRCode(qrCodeData); Bitmap qrCodeImage = qrCode.GetGraphic(20);

L'objet QRCode (' qrCode') défini appelle une fonction statique appelée ' BitmapToBytes()'. Le rôle de cette fonction est de convertir l'image Bitmap en ' Byte[]'.

Ajoutez cette fonction à votre contrôleur:

private static Byte[] BitmapToBytes(Bitmap img) { using (MemoryStream stream = new MemoryStream()) { img.Save(stream, System.Drawing.Imaging.ImageFormat.Png); return stream.ToArray(); } }

Enfin, créez la vue d'index dans le Views/QRCoderdossier ' ' avec le code suivant:

@model Byte[] @{ Layout = null; }     Implementing QRCoder in ASP.NET Core - Create QR Code  body { background: #111 no-repeat; background-image: -webkit-gradient(radial, 50% 0, 150, 50% 0, 300, from(#444), to(#111)); } h1, h2, h3 { text-align: center; color: #FFF; margin: 5px 0; } h1 { font-size: 30px; } h2 a { font-size: 25px; color: #0184e3; text-decoration: none; } h3 { font-size: 23px; border-bottom: solid 3px #CCC; padding-bottom: 10px; } h3 a { color: #00e8ff; text-decoration: none; } h3 a:hover, h2 a:hover { text-decoration: underline; } .container { width: 800px; margin: auto; color: #FFF; font-size: 25px; } .container #content { border: dashed 2px #CCC; padding: 10px; } #reset { padding: 5px 10px; background: #4CAF50; border: none; color: #FFF; cursor: pointer; } #reset:hover { color: #4CAF50; background: #FFF; } #viewContent table { width: 100%; } #viewContent table tr { height: 80px; background: darkcyan; } #viewContent table tr td { width: 50%; padding-left: 5px; } 

Implementing QRCoder in ASP.NET Core - Create QR Code

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@using (Html.BeginForm(null, null, FormMethod.Post)) {
Enter text for creating QR Code
Submit
} @{ if (Model != null) {

QR Code Successfully Generated

} }

La vue d'index a un inputcontrôle « ». L'utilisateur entre son texte dans ce champ pour créer le QR Code:

/>

Once the QR Code is generated by the Index Action method, its ‘byte’ array is returned to the View as model and then the bitmap image is displayed by the below code:

@{ if (Model != null) { 

QR Code Successfully Generated

} }

Testing the Code

Run your application and go to the URL — ‘//localhost:50755/QRCoder’ to invoke the Index Action method.

In the text box, add your text and click the submit button to create the QR Code Bitmap image.

See this image which illustrates it working:

Original text


Create QR Code File (.qrr) for any text and then save these files in the application

You can also generate QR Code files for a text and save it in your website. These files have .qrr extension.

To your controller add the following Action methods called ‘GenerateFile’:

public IActionResult GenerateFile() { return View(); } [HttpPost] public IActionResult GenerateFile(string qrText) { QRCodeGenerator qrGenerator = new QRCodeGenerator(); QRCodeData qrCodeData = qrGenerator.CreateQrCode(qrText, QRCodeGenerator.ECCLevel.Q); string fileGuid = Guid.NewGuid().ToString().Substring(0, 4); qrCodeData.SaveRawData("wwwroot/qrr/file-" + fileGuid + ".qrr", QRCodeData.Compression.Uncompressed); QRCodeData qrCodeData1 = new QRCodeData("wwwroot/qrr/file-" + fileGuid + ".qrr", QRCodeData.Compression.Uncompressed); QRCode qrCode = new QRCode(qrCodeData1); Bitmap qrCodeImage = qrCode.GetGraphic(20); return View(BitmapToBytes(qrCodeImage)); }

The [HttpPost] version of this action method generates the QR Code files inside the ‘wwwroot/qrr’ folder. The code that does this work is the following:

QRCodeGenerator qrGenerator = new QRCodeGenerator(); QRCodeData qrCodeData = qrGenerator.CreateQrCode(qrText, QRCodeGenerator.ECCLevel.Q); string fileGuid = Guid.NewGuid().ToString().Substring(0, 4); qrCodeData.SaveRawData("wwwroot/qrr/file-" + fileGuid + ".qrr", QRCodeData.Compression.Uncompressed);

Once the .qrr file is created then I am simply reading it for its saved location in the website. Then I am converting it to Bitmap type and finally sending the image’s bytes to the view. The corresponding code is:

QRCodeData qrCodeData1 = new QRCodeData("wwwroot/qrr/file-" + fileGuid + ".qrr", QRCodeData.Compression.Uncompressed); QRCode qrCode = new QRCode(qrCodeData1); Bitmap qrCodeImage = qrCode.GetGraphic(20); return View(BitmapToBytes(qrCodeImage));

Next, add the GenerateFile view inside the ‘Views/QRCoder’ folder and add the following code to it:

@model Byte[] @{ Layout = null; }     Implementing QRCoder in ASP.NET Core - Create QR Code File  body { background: #111 no-repeat; background-image: -webkit-gradient(radial, 50% 0, 150, 50% 0, 300, from(#444), to(#111)); } h1, h2, h3 { text-align: center; color: #FFF; margin: 5px 0; } h1 { font-size: 30px; } h2 a { font-size: 25px; color: #0184e3; text-decoration: none; } h3 { font-size: 23px; border-bottom: solid 3px #CCC; padding-bottom: 10px; } h3 a { color: #00e8ff; text-decoration: none; } h3 a:hover, h2 a:hover { text-decoration: underline; } .container { width: 800px; margin: auto; color: #FFF; font-size: 25px; } .container #content { border: dashed 2px #CCC; padding: 10px; } #reset { padding: 5px 10px; background: #4CAF50; border: none; color: #FFF; cursor: pointer; } #reset:hover { color: #4CAF50; background: #FFF; } #viewContent table { width: 100%; } #viewContent table tr { height: 80px; background: darkcyan; } #viewContent table tr td { width: 50%; padding-left: 5px; } 

Implementing QRCoder in ASP.NET Core - Create QR Code File

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@using (Html.BeginForm(null, null, FormMethod.Post)) {
Enter text for creating QR File
Submit
} @{ if (Model != null) {

QR Code file Successfully Generated

} }

The code of this View is exactly similar to the ‘Index’ View and works exactly like it.

The URL to invoke this View is ‘//localhost:50755/QRCoder/GenerateFile’.

Read and display all the QR Code Files (.qrr)

You can also read all the .qrr files saved in the website. Go to your controller and add a new action called ‘ViewFile’:

public IActionResult ViewFile() { List fileData=new List(); KeyValuePair data; string[] files = Directory.GetFiles("wwwroot/qrr"); foreach (string file in files) { QRCodeData qrCodeData = new QRCodeData(file, QRCodeData.Compression.Uncompressed); QRCode qrCode = new QRCode(qrCodeData); Bitmap qrCodeImage = qrCode.GetGraphic(20); Byte[] byteData = BitmapToBytes(qrCodeImage); data = new KeyValuePair(Path.GetFileName(file), byteData); fileData.Add(data); } return View(fileData); }

In this action method, I read the filed located in the ‘qrr’ folder using the code:

Directory.GetFiles("wwwroot/qrr")

Then I add each qrr file’s bytes and name inside a List object.

This object is returned to the View at the end:

return View(fileData);

Finally create the ‘ViewFile’ View inside the ‘Views/QRCoder’ folder with the following code:

@model List  @{ Layout = null; }     Implementing QRCoder in ASP.NET Core - View QR Code Files  body { background: #111 no-repeat; background-image: -webkit-gradient(radial, 50% 0, 150, 50% 0, 300, from(#444), to(#111)); } h1, h2, h3 { text-align: center; color: #FFF; margin: 5px 0; } h1 { font-size: 30px; } h2 a { font-size: 25px; color: #0184e3; text-decoration: none; } h3 { font-size: 23px; border-bottom: solid 3px #CCC; padding-bottom: 10px; } h3 a { color: #00e8ff; text-decoration: none; } h3 a:hover, h2 a:hover { text-decoration: underline; } .container { width: 800px; margin: auto; color: #FFF; font-size: 25px; } .container #content { border: dashed 2px #CCC; padding: 10px; } #reset { padding: 5px 10px; background: #4CAF50; border: none; color: #FFF; cursor: pointer; } #reset:hover { color: #4CAF50; background: #FFF; } #viewContent table { width: 100%; } #viewContent table tr { height: 80px; background: darkcyan; } #viewContent table tr td { width: 50%; padding-left: 5px; } #viewContent table tr td img { width: 150px; } #viewContent table tr td span { display: block; } 

Implementing QRCoder in ASP.NET Core - View QR Code Files

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@foreach (KeyValuePair k in Model) { }
@k.Key

This View displays all the qrr files as bitmap images inside a ‘HTML’ table. The below code creates the HTML table:

 @foreach (KeyValuePair k in Model) {  } 
@k.Key

Testing the Code

Run your application and go to the URL — ‘//localhost:50755/QRCoder/ViewFile’ to invoke the ViewFile Action method. You will see all the .qrr files saved in your website.

See the below image which illustrates it working:

You can download the full code from my GitHub Respositiory.

Conclusion

I hope you love this repository which will help you to use QRCoder in your ASP.NET Core Project. Make sure you like this repository to show your love to it.

If you need any help in ASP.NET Core then let me know in the below comments section.

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