ZXing - 使用泛型 BarcodeWriter<toutput> 需要 1 个类型参数 ZXing.NET.Mobile</toutput>

Question

I have been trying to generate a QRCode using ZXing.Net.Mobile and ZXing.Net.Mobile.Forms: https://github.com/Redth/ZXing.Net.Mobile and have come across the following error:

"Severity Code Description Project File Line Suppression State Error CS0305 Using the generic type 'BarcodeWriter' requires 1 type arguments TestApp.Android G:\Tests\TestApp\TestApp\TestApp.Android\SelectedBookingPage.cs 70 Active "

This is my code:

BarcodeWriter writer = new BarcodeWriter()
            {
                Format = BarcodeFormat.QR_CODE,
                Options = new ZXing.Common.EncodingOptions
                {
                    Height = 600,
                    Width = 600
                }
            };

Other examples I have seen call BarcodeWriter() like above just fine, https://csharp.hotexamples.com/examples/ZXing/BarcodeWriter/-/php-barcodewriter-class-examples.html to list a few.

Why does calling BarcodeWriter require a type argument. How can I properly instansiate an instance of a BarcodeWriter?

Answer 1

If you use ZXing.Net with.Net Standard, you have to add one additional package with a specific implementation of the barcode reader and writer classes for the image manipulation library that you want to use.

On Windows for example, you need to use this package: https://www.nuget.org/packages/ZXing.Net.Bindings.Windows.Compatibility/

more info here: https://github.com/micjahn/ZXing.Net/issues/370

Answer 2

The problem is you are using BarcodeWriter from the wrong namespace.

You should be using ZXing.Mobile.BarcodeWriter whereas you are using ZXing.BarcodeWriter , try the below and see if that works for you:

var barcodeWriter = new ZXing.Mobile.BarcodeWriter
        {
            Format = ZXing.BarcodeFormat.QR_CODE,
            Options = new ZXing.Common.EncodingOptions
            {
                Height = 600,
                Width = 600
            }
        };

Answer 3

I fixed the issue. BarcodeWriter can be instantiated as expected when used natively in the android project, in my original question I was attempting to use it within the cross platform Xamarin part of the project.