如何在C#中驗證條碼校驗和並使用格式感知讀取

Updated: 2026年6月29日

條碼校驗和有助於檢測替換錯誤。例如，在一個EAN-13標籤中，單一換位的數字可能會將包裹送到錯誤的倉庫。格式感知讀取通過限制解碼器到預期的符號學，提供了一個額外的驗證層。此方法降低了來自背景噪音的誤報，並通過跳過不必要的格式檢測器來縮短掃描時間。

IronBarcode在解碼過程中自動執行校驗和驗證。每個符號學的校驗位算法預設運行，並且失敗的條碼在結果返回之前被丟棄。 RemoveFalsePositive為模糊讀取增加了次要掃描。

本指南說明如何驗證條碼校驗和，將讀取限制在預期格式內，並使用BarcodeReaderOptions將這兩種技術結合成一個分層品質門。

快速入門：使用校驗和和格式限制驗證條碼

使用RemoveFalsePositive進行配置，以限制讀取到預期符號學，並自動執行校驗和驗證。

using IronBarCode;

// Format-constrained read with false-positive removal.
// Limit the decoder to EAN-13 and Code128; checksums are
// validated automatically and failures are silently discarded.
var options = new BarcodeReaderOptions
{
    ExpectBarcodeTypes  = BarcodeEncoding.EAN13 | BarcodeEncoding.Code128,
    RemoveFalsePositive = true,
    Speed               = ReadingSpeed.Balanced
};

BarcodeResults results = BarcodeReader.Read("label.png", options);

using IronBarCode;

// Format-constrained read with false-positive removal.
// Limit the decoder to EAN-13 and Code128; checksums are
// validated automatically and failures are silently discarded.
var options = new BarcodeReaderOptions
{
    ExpectBarcodeTypes  = BarcodeEncoding.EAN13 | BarcodeEncoding.Code128,
    RemoveFalsePositive = true,
    Speed               = ReadingSpeed.Balanced
};

BarcodeResults results = BarcodeReader.Read("label.png", options);

Imports IronBarCode

' Format-constrained read with false-positive removal.
' Limit the decoder to EAN-13 and Code128; checksums are
' validated automatically and failures are silently discarded.
Dim options As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.EAN13 Or BarcodeEncoding.Code128,
    .RemoveFalsePositive = True,
    .Speed = ReadingSpeed.Balanced
}

Dim results As BarcodeResults = BarcodeReader.Read("label.png", options)

Imports IronBarCode

' Format-constrained read with false-positive removal.
' Limit the decoder to EAN-13 and Code128; checksums are
' validated automatically and failures are silently discarded.
Dim options As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.EAN13 Or BarcodeEncoding.Code128,
    .RemoveFalsePositive = True,
    .Speed = ReadingSpeed.Balanced
}

Dim results As BarcodeResults = BarcodeReader.Read("label.png", options)

最小工作流程（5步）

從NuGet下載IronBarcode程式庫
建立一個BarcodeReaderOptions實例
將ExpectBarcodeTypes設置為管道中存在的符號學
啟用RemoveFalsePositive進行次要驗證
調用BarcodeReader.Read進行解碼，校驗和在解碼過程中自動驗證

如何驗證條碼校驗和？

IronBarcode根據每個符號學的規範在解碼過程中驗證校驗和。例如，當讀取一個EAN-13條碼時，Mod10校驗位是從前12位計算出來的並與第13位進行比對。如果數字不匹配，則條碼被默默拒絕，不會出現在BarcodeResults集中。此方法適用於所有具有強制校驗位的格式，包括UPC-A、UPC-E、EAN-8、Code128、ITF和其他格式。

這種隱含模式不同於那些顯示顯式切換的程式庫。下表比較了兩種方法：

校驗和驗證模型比較：IronBarcode vs. Aspose.BarCode
方面	IronBarcode	Aspose.BarCode
驗證觸發	自動；每次解碼時運行	Explicit: `ChecksumValidation.On` / `Off` / `Default`
需要的開發者操作	無；無效條碼從結果中排除	在讀取之前設置`BarcodeSettings.ChecksumValidation`
禁用校驗和	不公開；強制格式的校驗和始終執行	是的；`ChecksumValidation.Off`跳過驗證
可選校驗和格式（Code39）	使用`Confidence` + `RemoveFalsePositive`來過濾低質量讀取	顯式啟用`Enable校驗和.是的`
失敗行為	條碼在結果中默默被忽略	條碼可能會出現一個單獨的校驗和值進行手動檢查

對於具有可選校驗和的符號學，如Code39，程式庫使用信心評分和RemoveFalsePositive而不是校驗和切換。

輸入

一個Code128倉庫架標籤（成功路徑）和一個空白無條碼的圖片（失敗路徑）。

warehouse-rack.png（成功路徑）

blank-no-barcode.png（失敗路徑 — 無條碼）

using IronBarCode;

// Constrain reads to 1D formats and enable secondary verification.
// ConfidenceThreshold rejects decodes where the ML detector falls below 85%,
// acting as a quality gate for optional-checksum symbologies like Code39.
var options = new BarcodeReaderOptions
{
    ExpectBarcodeTypes  = BarcodeEncoding.AllOneDimensional,
    RemoveFalsePositive = true,
    ConfidenceThreshold = 0.85,
    Speed               = ReadingSpeed.Detailed
};

BarcodeResults results = BarcodeReader.Read("warehouse-rack.png", options);

foreach (BarcodeResult result in results)
{
    // Each result has passed checksum validation (mandatory formats)
    // and the 85% confidence threshold, so no additional filtering is needed.
    Console.WriteLine($"[{result.BarcodeType}] {result.Value}  page={result.PageNumber}");
}

if (results.Count == 0)
{
    Console.Error.WriteLine("No valid barcodes found. Possible causes:");
    Console.Error.WriteLine("  - Check digit mismatch (barcode silently rejected)");
    Console.Error.WriteLine("  - Confidence below 85% threshold");
    Console.Error.WriteLine("  - Format not in ExpectBarcodeTypes");
}

using IronBarCode;

// Constrain reads to 1D formats and enable secondary verification.
// ConfidenceThreshold rejects decodes where the ML detector falls below 85%,
// acting as a quality gate for optional-checksum symbologies like Code39.
var options = new BarcodeReaderOptions
{
    ExpectBarcodeTypes  = BarcodeEncoding.AllOneDimensional,
    RemoveFalsePositive = true,
    ConfidenceThreshold = 0.85,
    Speed               = ReadingSpeed.Detailed
};

BarcodeResults results = BarcodeReader.Read("warehouse-rack.png", options);

foreach (BarcodeResult result in results)
{
    // Each result has passed checksum validation (mandatory formats)
    // and the 85% confidence threshold, so no additional filtering is needed.
    Console.WriteLine($"[{result.BarcodeType}] {result.Value}  page={result.PageNumber}");
}

if (results.Count == 0)
{
    Console.Error.WriteLine("No valid barcodes found. Possible causes:");
    Console.Error.WriteLine("  - Check digit mismatch (barcode silently rejected)");
    Console.Error.WriteLine("  - Confidence below 85% threshold");
    Console.Error.WriteLine("  - Format not in ExpectBarcodeTypes");
}

Imports IronBarCode

' Constrain reads to 1D formats and enable secondary verification.
' ConfidenceThreshold rejects decodes where the ML detector falls below 85%,
' acting as a quality gate for optional-checksum symbologies like Code39.
Dim options As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.AllOneDimensional,
    .RemoveFalsePositive = True,
    .ConfidenceThreshold = 0.85,
    .Speed = ReadingSpeed.Detailed
}

Dim results As BarcodeResults = BarcodeReader.Read("warehouse-rack.png", options)

For Each result As BarcodeResult In results
    ' Each result has passed checksum validation (mandatory formats)
    ' and the 85% confidence threshold, so no additional filtering is needed.
    Console.WriteLine($"[{result.BarcodeType}] {result.Value}  page={result.PageNumber}")
Next

If results.Count = 0 Then
    Console.Error.WriteLine("No valid barcodes found. Possible causes:")
    Console.Error.WriteLine("  - Check digit mismatch (barcode silently rejected)")
    Console.Error.WriteLine("  - Confidence below 85% threshold")
    Console.Error.WriteLine("  - Format not in ExpectBarcodeTypes")
End If

Imports IronBarCode

' Constrain reads to 1D formats and enable secondary verification.
' ConfidenceThreshold rejects decodes where the ML detector falls below 85%,
' acting as a quality gate for optional-checksum symbologies like Code39.
Dim options As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.AllOneDimensional,
    .RemoveFalsePositive = True,
    .ConfidenceThreshold = 0.85,
    .Speed = ReadingSpeed.Detailed
}

Dim results As BarcodeResults = BarcodeReader.Read("warehouse-rack.png", options)

For Each result As BarcodeResult In results
    ' Each result has passed checksum validation (mandatory formats)
    ' and the 85% confidence threshold, so no additional filtering is needed.
    Console.WriteLine($"[{result.BarcodeType}] {result.Value}  page={result.PageNumber}")
Next

If results.Count = 0 Then
    Console.Error.WriteLine("No valid barcodes found. Possible causes:")
    Console.Error.WriteLine("  - Check digit mismatch (barcode silently rejected)")
    Console.Error.WriteLine("  - Confidence below 85% threshold")
    Console.Error.WriteLine("  - Format not in ExpectBarcodeTypes")
End If

輸出

成功路徑

倉庫架條碼在頁面0上顯示為BarcodeResults中。

失敗路徑

將ConfidenceThreshold從其0.7的預設值提高，進一步加強此門限，對於如Code39的可選校驗和符號學。

在涵蓋校驗和驗證後，下一步是將讀取器限制到您的管道所期望的條碼格式。

如何使用格式感知條碼讀取？

BarcodeEncoding枚舉是一個標誌型別，允許使用按位或運算符組合多個格式。設置ExpectBarcodeTypes將讀取限制在這些格式上，並跳過其他格式的檢測。

常見的BarcodeEncoding值
值	類別	描述	校驗和
`BarcodeEncoding.All`	後設	所有支持的格式（預設行為）	每格式
`BarcodeEncoding.AllOneDimensional`	後設	所有線性（1D）格式，包括堆疊的	每格式
`BarcodeEncoding.AllTwoDimensional`	後設	所有矩陣/網格（2D）格式	每格式
`BarcodeEncoding.Code128`	1D	高密度字母數字（物流，運輸）	強制（加權Mod103）
`BarcodeEncoding.EAN13`	1D	零售產品識別，13位數字	強制（Mod10）
`BarcodeEncoding.QRCode`	2D	高容量矩陣（URL，結構化資料）	里多索羅門ECC
`BarcodeEncoding.Code39`	1D	字母數字（國防，汽車）	可選（Mod43）
`BarcodeEncoding.UPCA`	1D	北美零售，12位數字	強制（Mod10）
`BarcodeEncoding.DataMatrix`	2D	緊湊矩陣（電子，製藥）	里多索羅門ECC
`BarcodeEncoding.PDF417`	2D	堆疊（身份證，運輸）	里多索羅門ECC

除了速度外，限制格式集還作為驗證門：任何未列出的符號學的條碼即使在圖像中實際存在，也從結果中排除。

輸入

一個Code128運單（成功路徑）和一個不符合Code128唯一限制條件的QR碼（失敗路徑）。

shipping-label.png（成功路徑 — Code128符合限制）

qr-format-mismatch.png（失敗路徑 — QR由Code128唯一過濾器拒絕）

using IronBarCode;

// Constrained read: only Code128 barcodes are returned.
// Faster because the reader skips all other format detectors.
var constrainedOptions = new BarcodeReaderOptions
{
    ExpectBarcodeTypes     = BarcodeEncoding.Code128,
    Speed                  = ReadingSpeed.Faster,
    ExpectMultipleBarcodes = false
};

// Broad read: all supported formats are scanned.
// Useful for verification or when the image format is unknown.
var broadOptions = new BarcodeReaderOptions
{
    ExpectBarcodeTypes     = BarcodeEncoding.All,
    Speed                  = ReadingSpeed.Detailed,
    ExpectMultipleBarcodes = true
};

string imagePath = "shipping-label.png";

BarcodeResults constrained = BarcodeReader.Read(imagePath, constrainedOptions);
Console.WriteLine($"Constrained: {constrained.Count} Code128 barcode(s) found");

BarcodeResults broad = BarcodeReader.Read(imagePath, broadOptions);
Console.WriteLine($"Broad: {broad.Count} barcode(s) found across all formats");

foreach (BarcodeResult result in broad)
{
    Console.WriteLine($"  [{result.BarcodeType}] {result.Value}");
}

using IronBarCode;

// Constrained read: only Code128 barcodes are returned.
// Faster because the reader skips all other format detectors.
var constrainedOptions = new BarcodeReaderOptions
{
    ExpectBarcodeTypes     = BarcodeEncoding.Code128,
    Speed                  = ReadingSpeed.Faster,
    ExpectMultipleBarcodes = false
};

// Broad read: all supported formats are scanned.
// Useful for verification or when the image format is unknown.
var broadOptions = new BarcodeReaderOptions
{
    ExpectBarcodeTypes     = BarcodeEncoding.All,
    Speed                  = ReadingSpeed.Detailed,
    ExpectMultipleBarcodes = true
};

string imagePath = "shipping-label.png";

BarcodeResults constrained = BarcodeReader.Read(imagePath, constrainedOptions);
Console.WriteLine($"Constrained: {constrained.Count} Code128 barcode(s) found");

BarcodeResults broad = BarcodeReader.Read(imagePath, broadOptions);
Console.WriteLine($"Broad: {broad.Count} barcode(s) found across all formats");

foreach (BarcodeResult result in broad)
{
    Console.WriteLine($"  [{result.BarcodeType}] {result.Value}");
}

Imports IronBarCode

' Constrained read: only Code128 barcodes are returned.
' Faster because the reader skips all other format detectors.
Dim constrainedOptions As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.Code128,
    .Speed = ReadingSpeed.Faster,
    .ExpectMultipleBarcodes = False
}

' Broad read: all supported formats are scanned.
' Useful for verification or when the image format is unknown.
Dim broadOptions As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.All,
    .Speed = ReadingSpeed.Detailed,
    .ExpectMultipleBarcodes = True
}

Dim imagePath As String = "shipping-label.png"

Dim constrained As BarcodeResults = BarcodeReader.Read(imagePath, constrainedOptions)
Console.WriteLine($"Constrained: {constrained.Count} Code128 barcode(s) found")

Dim broad As BarcodeResults = BarcodeReader.Read(imagePath, broadOptions)
Console.WriteLine($"Broad: {broad.Count} barcode(s) found across all formats")

For Each result As BarcodeResult In broad
    Console.WriteLine($"  [{result.BarcodeType}] {result.Value}")
Next

Imports IronBarCode

' Constrained read: only Code128 barcodes are returned.
' Faster because the reader skips all other format detectors.
Dim constrainedOptions As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.Code128,
    .Speed = ReadingSpeed.Faster,
    .ExpectMultipleBarcodes = False
}

' Broad read: all supported formats are scanned.
' Useful for verification or when the image format is unknown.
Dim broadOptions As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.All,
    .Speed = ReadingSpeed.Detailed,
    .ExpectMultipleBarcodes = True
}

Dim imagePath As String = "shipping-label.png"

Dim constrained As BarcodeResults = BarcodeReader.Read(imagePath, constrainedOptions)
Console.WriteLine($"Constrained: {constrained.Count} Code128 barcode(s) found")

Dim broad As BarcodeResults = BarcodeReader.Read(imagePath, broadOptions)
Console.WriteLine($"Broad: {broad.Count} barcode(s) found across all formats")

For Each result As BarcodeResult In broad
    Console.WriteLine($"  [{result.BarcodeType}] {result.Value}")
Next

輸出

成功路徑

運單的值是SHIP-2024-00438。受限讀取直接拾取它，因為Code128符合過濾器期望，而廣泛讀取在所有格式中證實同一結果。

失敗路徑

來自受限讀取的空結果是一個驗證信號，而不是錯誤；記錄該不一致以便審查。

對混合條碼型別的管道（例如，一個包括EAN-13產品程式碼和Code128追蹤號的包裝單），結合預期格式：

using IronBarCode;

// Combine multiple format flags with | to scan for more than one symbology
// in a single pass. Each BarcodeResult.BarcodeType identifies which format
// was decoded, enabling downstream routing logic per symbology.
var options = new BarcodeReaderOptions
{
    ExpectBarcodeTypes     = BarcodeEncoding.EAN13 | BarcodeEncoding.Code128,
    ExpectMultipleBarcodes = true
};

using IronBarCode;

// Combine multiple format flags with | to scan for more than one symbology
// in a single pass. Each BarcodeResult.BarcodeType identifies which format
// was decoded, enabling downstream routing logic per symbology.
var options = new BarcodeReaderOptions
{
    ExpectBarcodeTypes     = BarcodeEncoding.EAN13 | BarcodeEncoding.Code128,
    ExpectMultipleBarcodes = true
};

Imports IronBarCode

' Combine multiple format flags with Or to scan for more than one symbology
' in a single pass. Each BarcodeResult.BarcodeType identifies which format
' was decoded, enabling downstream routing logic per symbology.
Dim options As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.EAN13 Or BarcodeEncoding.Code128,
    .ExpectMultipleBarcodes = True
}

Imports IronBarCode

' Combine multiple format flags with Or to scan for more than one symbology
' in a single pass. Each BarcodeResult.BarcodeType identifies which format
' was decoded, enabling downstream routing logic per symbology.
Dim options As New BarcodeReaderOptions With {
    .ExpectBarcodeTypes = BarcodeEncoding.EAN13 Or BarcodeEncoding.Code128,
    .ExpectMultipleBarcodes = True
}

每個返回的BarcodeResult.BarcodeType識別被解碼的格式，支持下游路由。

哪些符號學支持校驗和驗證？

並不是所有條碼格式都以同樣的方式使用校驗和。下表將常見符號學映射到其錯誤檢測特性，這說明如何積極地設置RemoveFalsePositive為每種格式：

符號學的校驗和特性
符號學	校驗和型別	強制的？	建議
EAN-13 / EAN-8	Mod10	是的	預設設置足夠；始終執行校驗和
UPC-A / UPC-E	Mod10	是的	預設設置足夠；檢查位在寫入時自動糾正
Code128	加權Mod103	是的	預設設置足夠；按照規範強制執行
Code39	Mod43	可選	提升`ConfidenceThreshold`到0.8+並啟用`RemoveFalsePositive`
Codabar	Mod16	可選	與Code39相同；使用自信心作為質量門
ITF	Mod10	可選	啟用`RemoveFalsePositive`對交錯格式
QRCode / DataMatrix	里多索羅門ECC	始終	結構錯誤校正；不需要額外配置
PDF417	里多索羅門ECC	始終	與QR/DataMatrix相同；錯誤校正是固有的

對於如QR、DataMatrix和PDF417的2D符號學，錯誤校正在編碼結構中整合。這些格式可以從部分損壞中恢復，而不依賴於簡單的校驗位。 ConfidenceThreshold仍然適用於ML檢測階段，而解碼步驟受益於符號學的內建冗餘。

現在這兩種技術都已理解，讓我們將它們結合成一個單一的生產就緒驗證模式。

如何將校驗和與格式限制結合？

生產就緒模式在一個Speed。它們共同形成一個分層門：格式限制縮小搜索空間，校驗和驗證確保資料完整性，信心閾值對邊際解碼進行過濾，錯報刪除增加了次級驗證通過。

輸入

pos-scans/目錄中的三個POS掃描條碼被用作成功路徑：兩個EAN-13和一個UPC-A。一個Code128倉庫架標籤用作失敗路徑 — EAN-13/UPC-A限制拒絕它並記錄REJECT行。

EAN-13 barcode encoding 5901234123471 used as POS scan input 1

pos-scan-1.png（成功）

EAN-13 barcode encoding 4006381333931 used as POS scan input 2

pos-scan-2.png（成功）

UPC-A barcode encoding 012345678905 used as POS scan input 3

pos-scan-3.png（成功）

編碼 RACK-A1-LOT-7382 的 Code128 條碼，用作組合驗證失敗路徑的輸入

warehouse-rack.png（失敗 — Code128 被拒絕）

using IronBarCode;

// Layered validation for retail POS: EAN-13, UPC-A, and UPC-E only.
// Each property adds a distinct filter to the read pipeline.
var options = new BarcodeReaderOptions
{
    // Layer 1: format constraint, accept only retail symbologies
    ExpectBarcodeTypes = BarcodeEncoding.EAN13 | BarcodeEncoding.UPCA | BarcodeEncoding.UPCE,

    // Layer 2: confidence threshold, reject decodes below 80%
    ConfidenceThreshold = 0.8,

    // Layer 3: false-positive removal, runs a secondary verification pass
    RemoveFalsePositive = true,

    Speed                  = ReadingSpeed.Balanced,
    ExpectMultipleBarcodes = false,

    // Require 3 agreeing scan lines to reduce phantom reads from noisy images
    MinScanLines = 3
};

string[] scanFiles = Directory.GetFiles("pos-scans/", "*.png");

foreach (string file in scanFiles)
{
    BarcodeResults results = BarcodeReader.Read(file, options);

    if (results.Count == 0)
    {
        // No barcode passed all validation layers
        Console.Error.WriteLine($"REJECT {Path.GetFileName(file)}: "
            + "no valid EAN-13/UPC barcode (checksum, confidence, or format mismatch)");
        continue;
    }

    BarcodeResult primary = results.First();

    // Post-read assertion: verify the decoded format matches expectations.
    // ExpectBarcodeTypes already constrains the reader; this check documents
    // intent and surfaces unexpected results during future changes.
    if (primary.BarcodeType != BarcodeEncoding.EAN13
        && primary.BarcodeType != BarcodeEncoding.UPCA
        && primary.BarcodeType != BarcodeEncoding.UPCE)
    {
        Console.Error.WriteLine($"UNEXPECTED FORMAT {Path.GetFileName(file)}: "
            + $"got {primary.BarcodeType}, expected EAN-13/UPC");
        continue;
    }

    Console.WriteLine($"OK {Path.GetFileName(file)}: [{primary.BarcodeType}] {primary.Value}");
}

using IronBarCode;

// Layered validation for retail POS: EAN-13, UPC-A, and UPC-E only.
// Each property adds a distinct filter to the read pipeline.
var options = new BarcodeReaderOptions
{
    // Layer 1: format constraint, accept only retail symbologies
    ExpectBarcodeTypes = BarcodeEncoding.EAN13 | BarcodeEncoding.UPCA | BarcodeEncoding.UPCE,

    // Layer 2: confidence threshold, reject decodes below 80%
    ConfidenceThreshold = 0.8,

    // Layer 3: false-positive removal, runs a secondary verification pass
    RemoveFalsePositive = true,

    Speed                  = ReadingSpeed.Balanced,
    ExpectMultipleBarcodes = false,

    // Require 3 agreeing scan lines to reduce phantom reads from noisy images
    MinScanLines = 3
};

string[] scanFiles = Directory.GetFiles("pos-scans/", "*.png");

foreach (string file in scanFiles)
{
    BarcodeResults results = BarcodeReader.Read(file, options);

    if (results.Count == 0)
    {
        // No barcode passed all validation layers
        Console.Error.WriteLine($"REJECT {Path.GetFileName(file)}: "
            + "no valid EAN-13/UPC barcode (checksum, confidence, or format mismatch)");
        continue;
    }

    BarcodeResult primary = results.First();

    // Post-read assertion: verify the decoded format matches expectations.
    // ExpectBarcodeTypes already constrains the reader; this check documents
    // intent and surfaces unexpected results during future changes.
    if (primary.BarcodeType != BarcodeEncoding.EAN13
        && primary.BarcodeType != BarcodeEncoding.UPCA
        && primary.BarcodeType != BarcodeEncoding.UPCE)
    {
        Console.Error.WriteLine($"UNEXPECTED FORMAT {Path.GetFileName(file)}: "
            + $"got {primary.BarcodeType}, expected EAN-13/UPC");
        continue;
    }

    Console.WriteLine($"OK {Path.GetFileName(file)}: [{primary.BarcodeType}] {primary.Value}");
}

Imports IronBarCode
Imports System.IO

' Layered validation for retail POS: EAN-13, UPC-A, and UPC-E only.
' Each property adds a distinct filter to the read pipeline.
Dim options As New BarcodeReaderOptions With {
    ' Layer 1: format constraint, accept only retail symbologies
    .ExpectBarcodeTypes = BarcodeEncoding.EAN13 Or BarcodeEncoding.UPCA Or BarcodeEncoding.UPCE,

    ' Layer 2: confidence threshold, reject decodes below 80%
    .ConfidenceThreshold = 0.8,

    ' Layer 3: false-positive removal, runs a secondary verification pass
    .RemoveFalsePositive = True,

    .Speed = ReadingSpeed.Balanced,
    .ExpectMultipleBarcodes = False,

    ' Require 3 agreeing scan lines to reduce phantom reads from noisy images
    .MinScanLines = 3
}

Dim scanFiles As String() = Directory.GetFiles("pos-scans/", "*.png")

For Each file As String In scanFiles
    Dim results As BarcodeResults = BarcodeReader.Read(file, options)

    If results.Count = 0 Then
        ' No barcode passed all validation layers
        Console.Error.WriteLine($"REJECT {Path.GetFileName(file)}: " &
            "no valid EAN-13/UPC barcode (checksum, confidence, or format mismatch)")
        Continue For
    End If

    Dim primary As BarcodeResult = results.First()

    ' Post-read assertion: verify the decoded format matches expectations.
    ' ExpectBarcodeTypes already constrains the reader; this check documents
    ' intent and surfaces unexpected results during future changes.
    If primary.BarcodeType <> BarcodeEncoding.EAN13 AndAlso
       primary.BarcodeType <> BarcodeEncoding.UPCA AndAlso
       primary.BarcodeType <> BarcodeEncoding.UPCE Then
        Console.Error.WriteLine($"UNEXPECTED FORMAT {Path.GetFileName(file)}: " &
            $"got {primary.BarcodeType}, expected EAN-13/UPC")
        Continue For
    End If

    Console.WriteLine($"OK {Path.GetFileName(file)}: [{primary.BarcodeType}] {primary.Value}")
Next

Imports IronBarCode
Imports System.IO

' Layered validation for retail POS: EAN-13, UPC-A, and UPC-E only.
' Each property adds a distinct filter to the read pipeline.
Dim options As New BarcodeReaderOptions With {
    ' Layer 1: format constraint, accept only retail symbologies
    .ExpectBarcodeTypes = BarcodeEncoding.EAN13 Or BarcodeEncoding.UPCA Or BarcodeEncoding.UPCE,

    ' Layer 2: confidence threshold, reject decodes below 80%
    .ConfidenceThreshold = 0.8,

    ' Layer 3: false-positive removal, runs a secondary verification pass
    .RemoveFalsePositive = True,

    .Speed = ReadingSpeed.Balanced,
    .ExpectMultipleBarcodes = False,

    ' Require 3 agreeing scan lines to reduce phantom reads from noisy images
    .MinScanLines = 3
}

Dim scanFiles As String() = Directory.GetFiles("pos-scans/", "*.png")

For Each file As String In scanFiles
    Dim results As BarcodeResults = BarcodeReader.Read(file, options)

    If results.Count = 0 Then
        ' No barcode passed all validation layers
        Console.Error.WriteLine($"REJECT {Path.GetFileName(file)}: " &
            "no valid EAN-13/UPC barcode (checksum, confidence, or format mismatch)")
        Continue For
    End If

    Dim primary As BarcodeResult = results.First()

    ' Post-read assertion: verify the decoded format matches expectations.
    ' ExpectBarcodeTypes already constrains the reader; this check documents
    ' intent and surfaces unexpected results during future changes.
    If primary.BarcodeType <> BarcodeEncoding.EAN13 AndAlso
       primary.BarcodeType <> BarcodeEncoding.UPCA AndAlso
       primary.BarcodeType <> BarcodeEncoding.UPCE Then
        Console.Error.WriteLine($"UNEXPECTED FORMAT {Path.GetFileName(file)}: " &
            $"got {primary.BarcodeType}, expected EAN-13/UPC")
        Continue For
    End If

    Console.WriteLine($"OK {Path.GetFileName(file)}: [{primary.BarcodeType}] {primary.Value}")
Next

輸出

成功路徑

所有三個POS掃描圖像均成功通過。讀取器返回012345678905的值。每個都匹配EAN13| UPCA| UPCE過濾器，具有有效的Mod10校驗和，並且信心高於0.8。

失敗路徑

將MinScanLines設置為3增加1D條碼有效所需的一致掃描線的最小數量；預設值是2。提高此數值降低了來自噪聲掃描線的幽靈讀取風險，但可能導致錯過細或部分受損的條碼。在零售POS環境中，使用乾淨的印刷標籤，數值3是一個保守的選擇，增強驗證而不影響吞吐量。

讀取後的ReadingSpeed.Faster適合乾淨的機器印刷標籤； ExtremeDetail在掃描時間更長的情況下恢復受損或光照不足的條碼。

我的下一步是什麼？

本文介紹了IronBarcode的隱含校驗和驗證模型、格式受限讀取的MinScanLines作為層次質量門的綜合驗證模式。

要進一步閱讀，請探索這些資源：

IronBarcode教程 — 條碼讀取，提供端到端的讀取演練。
防止誤報，詳細說明RemoveFalsePositive機制。
信心閾值範例，進行基於ML的檢測調整。
輸出資料格式，參考BarcodeResult屬性。
圖像校正操作指南，介紹提高解碼準確性的過濾器。
BarcodeReaderOptions API參考，提供完整的配置文件。
BarcodeEncoding API參考，提供支持的符號學的完整清單。

獲取免費試用授權以在現場環境中測試每一個功能，或者當管道準備好生產時，查看授權選項。

常見問題

什麼是條碼校驗碼驗證？

條碼校驗碼驗證是一個確保條碼資料準確性的過程，通過將計算得出的校驗碼與條碼中編碼的值進行驗證。這有助於在掃描過程中檢測錯誤。

IronBarcode如何處理校驗碼驗證？

IronBarcode隱式地處理校驗碼驗證，通過計算條碼資料的校驗碼並將其與編碼校驗碼相比較，確保在掃描過程中的資料完整性。

什麼是BarcodeEncoding過濾器？

IronBarcode的BarcodeEncoding過濾器允許您指定在掃描中要讀取或忽略的條碼格式，通過專注於特定的條碼型別來實現更準確和有效的條碼處理。

IronBarcode可以進行組合驗證嗎？

是的，IronBarcode可以在掃描過程中通過檢查條碼的校驗碼和格式進行組合驗證，確保僅處理有效和格式正確的條碼。

在C#中使用IronBarcode限制格式進行條碼讀取是否可行？

是的，IronBarcode允許您通過指定要包括或排除的格式來限制條碼讀取，確保您的應用程式僅處理相關的條碼型別。

為什麼格式感知讀取在條碼處理中很重要？

格式感知讀取很重要，因為它允許您的應用程式僅處理特定型別的條碼，通過忽略不相關或不支持的條碼格式來提高速度和準確性。

如何在IronBarcode中實現格式感知讀取？

要在IronBarcode中實現格式感知讀取，使用BarcodeEncoding過濾器指定您希望讀取的條碼格式。這可以通過該程式庫的API完成，允許對條碼掃描要求進行精確控制。

使用IronBarcode進行條碼驗證有哪些好處？

IronBarcode在條碼驗證中提供幾個好處，包括強大的校驗碼驗證、格式感知讀取以及處理多種條碼標準的能力，確保條碼處理的高準確性和靈活性。

What does the ConfidenceThreshold property do in IronBarcode?

The `ConfidenceThreshold` property in IronBarcode sets a quality gate for decoding, rejecting barcodes where the machine learning detector's confidence falls below a specified percentage.

How can IronBarcode combine checksum validation with format constraints?

IronBarcode combines checksum validation with format constraints using `BarcodeReaderOptions`. By setting properties like `ExpectBarcodeTypes`, `ConfidenceThreshold`, and `RemoveFalsePositive`, it creates a layered validation approach.