.NET MAUI で Android のバーコードを読み書きする方法

using IronBarCode;
using System;
using System.IO;
using System.Threading.Tasks;
using Xamarin.Essentials;

namespace IronBarcodeMauiAndroid
{
    public partial class MainPage : ContentPage
    {
        public bool IsGeneratePdfChecked
        {
            get => generatePdfCheckBox.IsChecked;
            set
            {
                generatePdfCheckBox.IsChecked = value;
            }
        }

        public MainPage()
        {
            InitializeComponent();
            // Set the license key for IronBarcode, replace with your actual license key.
            License.LicenseKey = "IRONBARCODE-MYLICENSE-KEY-1EF01";
        }

        private async void WriteBarcode(object sender, EventArgs e)
        {
            try
            {
                if (!string.IsNullOrEmpty(barcodeInput.Text))
                {
                    // Create a barcode from the text input with the EAN13 encoding.
                    var barcode = BarcodeWriter.CreateBarcode(barcodeInput.Text, BarcodeEncoding.EAN13);

                    // Determine the file extension and data format based on the checkbox state.
                    string fileExtension = IsGeneratePdfChecked ? "pdf" : "png";
                    string fileName = $"Barcode_{DateTime.Now:yyyyMMddHHmmss}.{fileExtension}";
                    byte[] fileData = IsGeneratePdfChecked ? barcode.ToPdfBinaryData() : barcode.ToPngBinaryData();

                    // Save the generated barcode to the Downloads folder.
                    await SaveToDownloadsAsync(fileData, fileName);

                    await Application.Current.MainPage.DisplayAlert("Saved", "File saved to Downloads folder", "OK");
                }
            }
            catch (Exception ex)
            {
                // Handle exceptions and log the error.
                System.Diagnostics.Debug.WriteLine(ex);
            }
        }

        private async void WriteQRcode(object sender, EventArgs e)
        {
            try
            {
                if (!string.IsNullOrEmpty(qrInput.Text))
                {
                    // Create a QR code from the text input.
                    var barcode = QRCodeWriter.CreateQrCode(qrInput.Text);

                    // Determine the file extension and data format based on the checkbox state.
                    string fileExtension = IsGeneratePdfChecked ? "pdf" : "png";
                    string fileName = $"QRcode_{DateTime.Now:yyyyMMddHHmmss}.{fileExtension}";
                    byte[] fileData = IsGeneratePdfChecked ? barcode.ToPdfBinaryData() : barcode.ToPngBinaryData();

                    // Save the generated QR code to the Downloads folder.
                    await SaveToDownloadsAsync(fileData, fileName);

                    await Application.Current.MainPage.DisplayAlert("Saved", "File saved to Downloads folder", "OK");
                }
            }
            catch (Exception ex)
            {
                // Handle exceptions and log the error.
                System.Diagnostics.Debug.WriteLine(ex);
            }
        }

        private async void ReadBarcode(object sender, EventArgs e)
        {
            try
            {
                var options = new PickOptions
                {
                    PickerTitle = "Please select a file"
                };
                var file = await FilePicker.PickAsync(options);

                OutputText.Text = "";

                if (file != null)
                {
                    using var stream = await file.OpenReadAsync();

                    BarcodeResults result;

                    if (file.ContentType.Contains("image"))
                    {
                        // Read barcodes from an image file.
                        result = BarcodeReader.Read(stream);
                    }
                    else
                    {
                        // Read barcodes from a PDF file.
                        result = BarcodeReader.ReadPdf(stream);
                    }

                    string barcodeResult = "";
                    int count = 1;

                    // Retrieve and format the barcode reading results.
                    result.ForEach(x => { barcodeResult += $"Barcode {count}: {x.Value}\n"; count++; });

                    OutputText.Text = barcodeResult;
                }
            }
            catch (Exception ex)
            {
                // Handle exceptions and log the error.
                System.Diagnostics.Debug.WriteLine(ex);
            }
        }

        public async Task SaveToDownloadsAsync(byte[] fileData, string fileName)
        {
            var downloadsPath = Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DirectoryDownloads);
            var filePath = Path.Combine(downloadsPath.AbsolutePath, fileName);

            try
            {
                // Create the directory if it doesn't exist.
                if (!Directory.Exists(downloadsPath.AbsolutePath))
                {
                    Directory.CreateDirectory(downloadsPath.AbsolutePath);
                }

                // Save the file to the Downloads folder.
                await File.WriteAllBytesAsync(filePath, fileData);
            }
            catch (Exception ex)
            {
                // Log errors if file saving fails.
                System.Diagnostics.Debug.WriteLine("Error saving file: " + ex.Message);
            }
        }
    }
}

Imports Microsoft.VisualBasic
Imports IronBarCode
Imports System
Imports System.IO
Imports System.Threading.Tasks
Imports Xamarin.Essentials

Namespace IronBarcodeMauiAndroid
	Partial Public Class MainPage
		Inherits ContentPage

		Public Property IsGeneratePdfChecked() As Boolean
			Get
				Return generatePdfCheckBox.IsChecked
			End Get
			Set(ByVal value As Boolean)
				generatePdfCheckBox.IsChecked = value
			End Set
		End Property

		Public Sub New()
			InitializeComponent()
			' Set the license key for IronBarcode, replace with your actual license key.
			License.LicenseKey = "IRONBARCODE-MYLICENSE-KEY-1EF01"
		End Sub

		Private Async Sub WriteBarcode(ByVal sender As Object, ByVal e As EventArgs)
			Try
				If Not String.IsNullOrEmpty(barcodeInput.Text) Then
					' Create a barcode from the text input with the EAN13 encoding.
					Dim barcode = BarcodeWriter.CreateBarcode(barcodeInput.Text, BarcodeEncoding.EAN13)

					' Determine the file extension and data format based on the checkbox state.
					Dim fileExtension As String = If(IsGeneratePdfChecked, "pdf", "png")
					Dim fileName As String = $"Barcode_{DateTime.Now:yyyyMMddHHmmss}.{fileExtension}"
					Dim fileData() As Byte = If(IsGeneratePdfChecked, barcode.ToPdfBinaryData(), barcode.ToPngBinaryData())

					' Save the generated barcode to the Downloads folder.
					Await SaveToDownloadsAsync(fileData, fileName)

					Await Application.Current.MainPage.DisplayAlert("Saved", "File saved to Downloads folder", "OK")
				End If
			Catch ex As Exception
				' Handle exceptions and log the error.
				System.Diagnostics.Debug.WriteLine(ex)
			End Try
		End Sub

		Private Async Sub WriteQRcode(ByVal sender As Object, ByVal e As EventArgs)
			Try
				If Not String.IsNullOrEmpty(qrInput.Text) Then
					' Create a QR code from the text input.
					Dim barcode = QRCodeWriter.CreateQrCode(qrInput.Text)

					' Determine the file extension and data format based on the checkbox state.
					Dim fileExtension As String = If(IsGeneratePdfChecked, "pdf", "png")
					Dim fileName As String = $"QRcode_{DateTime.Now:yyyyMMddHHmmss}.{fileExtension}"
					Dim fileData() As Byte = If(IsGeneratePdfChecked, barcode.ToPdfBinaryData(), barcode.ToPngBinaryData())

					' Save the generated QR code to the Downloads folder.
					Await SaveToDownloadsAsync(fileData, fileName)

					Await Application.Current.MainPage.DisplayAlert("Saved", "File saved to Downloads folder", "OK")
				End If
			Catch ex As Exception
				' Handle exceptions and log the error.
				System.Diagnostics.Debug.WriteLine(ex)
			End Try
		End Sub

		Private Async Sub ReadBarcode(ByVal sender As Object, ByVal e As EventArgs)
			Try
				Dim options = New PickOptions With {.PickerTitle = "Please select a file"}
				Dim file = Await FilePicker.PickAsync(options)

				OutputText.Text = ""

				If file IsNot Nothing Then
					Dim stream = Await file.OpenReadAsync()

					Dim result As BarcodeResults

					If file.ContentType.Contains("image") Then
						' Read barcodes from an image file.
						result = BarcodeReader.Read(stream)
					Else
						' Read barcodes from a PDF file.
						result = BarcodeReader.ReadPdf(stream)
					End If

					Dim barcodeResult As String = ""
					Dim count As Integer = 1

					' Retrieve and format the barcode reading results.
					result.ForEach(Sub(x)
						barcodeResult &= $"Barcode {count}: {x.Value}" & vbLf
						count += 1
					End Sub)

					OutputText.Text = barcodeResult
				End If
			Catch ex As Exception
				' Handle exceptions and log the error.
				System.Diagnostics.Debug.WriteLine(ex)
			End Try
		End Sub

		Public Async Function SaveToDownloadsAsync(ByVal fileData() As Byte, ByVal fileName As String) As Task
			Dim downloadsPath = Android.OS.Environment.GetExternalStoragePublicDirectory(Android.OS.Environment.DirectoryDownloads)
			Dim filePath = Path.Combine(downloadsPath.AbsolutePath, fileName)

			Try
				' Create the directory if it doesn't exist.
				If Not Directory.Exists(downloadsPath.AbsolutePath) Then
					Directory.CreateDirectory(downloadsPath.AbsolutePath)
				End If

				' Save the file to the Downloads folder.
				Await File.WriteAllBytesAsync(filePath, fileData)
			Catch ex As Exception
				' Log errors if file saving fails.
				System.Diagnostics.Debug.WriteLine("Error saving file: " & ex.Message)
			End Try
		End Function
	End Class
End Namespace