// ZXing.Net: full reader instantiation and configuration on every parallel task
Parallel.ForEach(files, file =>
{
    var reader = new BarcodeReader();
    reader.Options.PossibleFormats = new List<BarcodeFormat>
    {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.EAN_13
    };

    using var bitmap = new Bitmap(file);
    var result = reader.Decode(bitmap);
    if (result != null)
        processed[file] = result.Text;
});

Imports ZXing
Imports System.Drawing
Imports System.Threading.Tasks

Parallel.ForEach(files, Sub(file)
    Dim reader As New BarcodeReader()
    reader.Options.PossibleFormats = New List(Of BarcodeFormat) From {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.EAN_13
    }

    Using bitmap As New Bitmap(file)
        Dim result = reader.Decode(bitmap)
        If result IsNot Nothing Then
            processed(file) = result.Text
        End If
    End Using
End Sub)

// IronBarcode: static call, same code for single-threaded and concurrent use
Parallel.ForEach(files, file =>
{
    var result = BarcodeReader.Read(file).FirstOrDefault();
    if (result != null)
        processed[file] = result.Value;
});

Imports IronBarCode
Imports System.Threading.Tasks

Parallel.ForEach(files, Sub(file)
    Dim result = BarcodeReader.Read(file).FirstOrDefault()
    If result IsNot Nothing Then
        processed(file) = result.Value
    End If
End Sub)

dotnet remove package ZXing.Net
dotnet remove package ZXing.Net.Bindings.Windows.Compatibility
dotnet remove package ZXing.Net.Bindings.ImageSharp
dotnet remove package PdfiumViewer

dotnet remove package PdfiumViewer.Native.x64.v8-xfa

dotnet add package IronBarcode

// Remove all of these:
using ZXing;
using ZXing.Common;
using ZXing.Windows.Compatibility;
using ZXing.ImageSharp;
using SixLabors.ImageSharp;
using SixLabors.ImageSharp.PixelFormats;
using PdfiumViewer;

// Add this single import:
using IronBarCode;

Imports IronBarCode

// Program.cs or Startup.cs — initialise once at startup
IronBarCode.License.LicenseKey = "YOUR-LICENSE-KEY";

' Program.vb or Startup.vb — initialise once at startup
IronBarCode.License.LicenseKey = "YOUR-LICENSE-KEY"

using ZXing;
using ZXing.Windows.Compatibility;
using System.Drawing;

public string ReadSingleBarcode(string imagePath)
{
    var reader = new BarcodeReader();
    reader.Options.PossibleFormats = new List<BarcodeFormat>
    {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.EAN_13
    };

    using var bitmap = new Bitmap(imagePath);
    var result = reader.Decode(bitmap);

    return result?.Text ?? string.Empty;
}

Imports ZXing
Imports ZXing.Windows.Compatibility
Imports System.Drawing

Public Function ReadSingleBarcode(imagePath As String) As String
    Dim reader = New BarcodeReader()
    reader.Options.PossibleFormats = New List(Of BarcodeFormat) From {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.EAN_13
    }

    Using bitmap As New Bitmap(imagePath)
        Dim result = reader.Decode(bitmap)
        Return If(result?.Text, String.Empty)
    End Using
End Function

using IronBarCode;

public string ReadSingleBarcode(string imagePath)
{
    var result = BarcodeReader.Read(imagePath).FirstOrDefault();
    return result?.Value ?? string.Empty;
}

Imports IronBarCode

Public Function ReadSingleBarcode(imagePath As String) As String
    Dim result = BarcodeReader.Read(imagePath).FirstOrDefault()
    Return If(result?.Value, String.Empty)
End Function

using ZXing;
using ZXing.Windows.Compatibility;
using System.Drawing;

public List<string> ReadAllBarcodes(string imagePath)
{
    var reader = new BarcodeReader();
    reader.Options.PossibleFormats = new List<BarcodeFormat>
    {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.CODE_39,
        BarcodeFormat.EAN_13,
        BarcodeFormat.EAN_8,
        BarcodeFormat.UPC_A,
        BarcodeFormat.DATA_MATRIX,
        BarcodeFormat.PDF_417
    };
    reader.Options.TryHarder = true;

    using var bitmap = new Bitmap(imagePath);
    var results = reader.DecodeMultiple(bitmap);

    return results?.Select(r => r.Text).ToList() ?? new List<string>();
}

Imports ZXing
Imports ZXing.Windows.Compatibility
Imports System.Drawing

Public Function ReadAllBarcodes(imagePath As String) As List(Of String)
    Dim reader = New BarcodeReader()
    reader.Options.PossibleFormats = New List(Of BarcodeFormat) From {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.CODE_39,
        BarcodeFormat.EAN_13,
        BarcodeFormat.EAN_8,
        BarcodeFormat.UPC_A,
        BarcodeFormat.DATA_MATRIX,
        BarcodeFormat.PDF_417
    }
    reader.Options.TryHarder = True

    Using bitmap As New Bitmap(imagePath)
        Dim results = reader.DecodeMultiple(bitmap)
        Return If(results?.Select(Function(r) r.Text).ToList(), New List(Of String)())
    End Using
End Function

using IronBarCode;

public List<string> ReadAllBarcodes(string imagePath)
{
    return BarcodeReader.Read(imagePath)
        .Select(r => r.Value)
        .ToList();
}

Imports IronBarCode

Public Function ReadAllBarcodes(imagePath As String) As List(Of String)
    Return BarcodeReader.Read(imagePath) _
        .Select(Function(r) r.Value) _
        .ToList()
End Function

using ZXing;
using ZXing.Windows.Compatibility;
using System.Collections.Concurrent;
using System.Drawing;

public Dictionary<string, string> ProcessBatch(IEnumerable<string> filePaths)
{
    var output = new ConcurrentDictionary<string, string>();

    Parallel.ForEach(filePaths, new ParallelOptions { MaxDegreeOfParallelism = 4 }, file =>
    {
        // ZXing.Net is not thread-safe — a new reader is required per parallel operation
        var reader = new BarcodeReader();
        reader.Options.PossibleFormats = new List<BarcodeFormat>
        {
            BarcodeFormat.QR_CODE,
            BarcodeFormat.CODE_128
        };

        using var bitmap = new Bitmap(file);
        var result = reader.Decode(bitmap);
        if (result != null)
            output[file] = result.Text;
    });

    return output.ToDictionary(kvp => kvp.Key, kvp => kvp.Value);
}

Imports ZXing
Imports ZXing.Windows.Compatibility
Imports System.Collections.Concurrent
Imports System.Drawing

Public Function ProcessBatch(filePaths As IEnumerable(Of String)) As Dictionary(Of String, String)
    Dim output = New ConcurrentDictionary(Of String, String)()

    Parallel.ForEach(filePaths, New ParallelOptions With {.MaxDegreeOfParallelism = 4}, Sub(file)
        ' ZXing.Net is not thread-safe — a new reader is required per parallel operation
        Dim reader = New BarcodeReader()
        reader.Options.PossibleFormats = New List(Of BarcodeFormat) From {
            BarcodeFormat.QR_CODE,
            BarcodeFormat.CODE_128
        }

        Using bitmap As New Bitmap(file)
            Dim result = reader.Decode(bitmap)
            If result IsNot Nothing Then
                output(file) = result.Text
            End If
        End Using
    End Sub)

    Return output.ToDictionary(Function(kvp) kvp.Key, Function(kvp) kvp.Value)
End Function

using IronBarCode;
using System.Collections.Concurrent;

public Dictionary<string, string> ProcessBatch(IEnumerable<string> filePaths)
{
    var output = new ConcurrentDictionary<string, string>();
    var options = new BarcodeReaderOptions { MaxParallelThreads = 4 };

    Parallel.ForEach(filePaths, file =>
    {
        var result = BarcodeReader.Read(file, options).FirstOrDefault();
        if (result != null)
            output[file] = result.Value;
    });

    return output.ToDictionary(kvp => kvp.Key, kvp => kvp.Value);
}

Imports IronBarCode
Imports System.Collections.Concurrent

Public Function ProcessBatch(filePaths As IEnumerable(Of String)) As Dictionary(Of String, String)
    Dim output = New ConcurrentDictionary(Of String, String)()
    Dim options = New BarcodeReaderOptions With {.MaxParallelThreads = 4}

    Parallel.ForEach(filePaths, Sub(file)
        Dim result = BarcodeReader.Read(file, options).FirstOrDefault()
        If result IsNot Nothing Then
            output(file) = result.Value
        End If
    End Sub)

    Return output.ToDictionary(Function(kvp) kvp.Key, Function(kvp) kvp.Value)
End Function

using ZXing;
using ZXing.Windows.Compatibility;
using PdfiumViewer;
using System.Drawing;
using System.Drawing.Imaging;

public List<string> ExtractBarcodesFromPdf(string pdfPath)
{
    var collected = new List<string>();

    var reader = new BarcodeReader();
    reader.Options.PossibleFormats = new List<BarcodeFormat>
    {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.PDF_417
    };

    using var document = PdfDocument.Load(pdfPath);
    for (int page = 0; page < document.PageCount; page++)
    {
        string temp = Path.Combine(Path.GetTempPath(), $"{Guid.NewGuid()}.png");
        try
        {
            using var rendered = document.Render(page, 200, 200, PdfRenderFlags.CorrectFromDpi);
            rendered.Save(temp, ImageFormat.Png);

            using var bmp = new Bitmap(temp);
            var decoded = reader.DecodeMultiple(bmp);
            if (decoded != null)
                collected.AddRange(decoded.Select(d => d.Text));
        }
        finally
        {
            if (File.Exists(temp))
                File.Delete(temp);
        }
    }

    return collected;
}

Imports ZXing
Imports ZXing.Windows.Compatibility
Imports PdfiumViewer
Imports System.Drawing
Imports System.Drawing.Imaging

Public Function ExtractBarcodesFromPdf(pdfPath As String) As List(Of String)
    Dim collected As New List(Of String)()

    Dim reader As New BarcodeReader()
    reader.Options.PossibleFormats = New List(Of BarcodeFormat) From {
        BarcodeFormat.QR_CODE,
        BarcodeFormat.CODE_128,
        BarcodeFormat.PDF_417
    }

    Using document = PdfDocument.Load(pdfPath)
        For page As Integer = 0 To document.PageCount - 1
            Dim temp As String = Path.Combine(Path.GetTempPath(), $"{Guid.NewGuid()}.png")
            Try
                Using rendered = document.Render(page, 200, 200, PdfRenderFlags.CorrectFromDpi)
                    rendered.Save(temp, ImageFormat.Png)

                    Using bmp As New Bitmap(temp)
                        Dim decoded = reader.DecodeMultiple(bmp)
                        If decoded IsNot Nothing Then
                            collected.AddRange(decoded.Select(Function(d) d.Text))
                        End If
                    End Using
                End Using
            Finally
                If File.Exists(temp) Then
                    File.Delete(temp)
                End If
            End Try
        Next
    End Using

    Return collected
End Function

using IronBarCode;

public List<string> ExtractBarcodesFromPdf(string pdfPath)
{
    return BarcodeReader.Read(pdfPath)
        .Select(r => r.Value)
        .ToList();
}

Imports IronBarCode

Public Function ExtractBarcodesFromPdf(pdfPath As String) As List(Of String)
    Return BarcodeReader.Read(pdfPath) _
        .Select(Function(r) r.Value) _
        .ToList()
End Function

using ZXing;
using ZXing.Common;
using ZXing.Windows.Compatibility;
using System.Drawing;
using System.Drawing.Imaging;

public void WriteCode128(string content, string outputPath)
{
    var writer = new BarcodeWriter
    {
        Format = BarcodeFormat.CODE_128,
        Options = new EncodingOptions
        {
            Width = 400,
            Height = 120,
            Margin = 10
        }
    };

    using var bitmap = writer.Write(content);
    bitmap.Save(outputPath, ImageFormat.Png);
}

Imports ZXing
Imports ZXing.Common
Imports ZXing.Windows.Compatibility
Imports System.Drawing
Imports System.Drawing.Imaging

Public Sub WriteCode128(content As String, outputPath As String)
    Dim writer = New BarcodeWriter With {
        .Format = BarcodeFormat.CODE_128,
        .Options = New EncodingOptions With {
            .Width = 400,
            .Height = 120,
            .Margin = 10
        }
    }

    Using bitmap = writer.Write(content)
        bitmap.Save(outputPath, ImageFormat.Png)
    End Using
End Sub

using IronBarCode;

public void WriteCode128(string content, string outputPath)
{
    BarcodeWriter.CreateBarcode(content, BarcodeEncoding.Code128)
        .ResizeTo(400, 120)
        .SaveAsPng(outputPath);
}

Imports IronBarCode

Public Sub WriteCode128(content As String, outputPath As String)
    BarcodeWriter.CreateBarcode(content, BarcodeEncoding.Code128) _
        .ResizeTo(400, 120) _
        .SaveAsPng(outputPath)
End Sub

// Before: reader creation + format config + bitmap + decode + result.Text
// After:
var result = BarcodeReader.Read(imagePath).FirstOrDefault();
var value = result?.Value ?? string.Empty;

' Before: reader creation + format config + bitmap + decode + result.Text
' After:
Dim result = BarcodeReader.Read(imagePath).FirstOrDefault()
Dim value = If(result?.Value, String.Empty)

grep -r "using ZXing" --include="*.cs" .
grep -r "new BarcodeReader" --include="*.cs" .
grep -r "PossibleFormats" --include="*.cs" .
grep -r "BarcodeFormat\." --include="*.cs" .
grep -r "reader\.Decode\|reader\.DecodeMultiple" --include="*.cs" .
grep -r "result\.Text\|result\.BarcodeFormat" --include="*.cs" .
grep -r "new BarcodeWriter\|writer\.Write\|EncodingOptions" --include="*.cs" .
grep -r "PdfiumViewer\|PdfDocument\.Load" --include="*.cs" .
grep -r "using System\.Drawing" --include="*.cs" .