如何在WPF中建立QR Code掃描器

Updated: 2026年3月4日

Windows Presentation Foundation (WPF) 是一個.NET框架，用於建立具有XAML定義UI的Windows桌面應用程式。 IronQR直接整合到WPF中，只需幾行C#程式碼即可從使用者選擇的圖像文件中掃描QR Code。

在本指南中，我們將建立一個WPF應用程式，打開文件對話框，載入選擇的圖像，並使用IronQR解碼任何嵌入的QR Code。該方法支援PNG、JPEG、BMP、GIF、TIFF及其他常見圖像格式。

如何在WPF中掃描QR Code

透過NuGet安裝IronQR C#程式庫
在XAML中向WPF窗口新增Button和TextBlock
使用OpenFileDialog打開文件對話框，從磁碟中選擇圖像
使用AnyBitmap.FromFile載入圖像並將其包裝在QrImageInput中
呼叫Read，並在TextBlock中顯示解碼後的值

先決條件

安裝**.NET桌面開發**工作負載的Visual Studio 2022
目標為.NET 8或更高版本的WPF專案

安裝IronQR

使用Visual Studio中的NuGet套件管理器控制台安裝IronQR程式庫。導航至工具 > NuGet Package Manager > Package Manager Console並運行：

PM > Install-Package IronQR

Install-Package IronQR

或者，在NuGet上搜尋IronQR並安裝最新版本。

WPF窗口佈局

掃描器UI使用TextBlock顯示解碼結果。向MainWindow.xaml新增以下標記：

<StackPanel Margin="28" VerticalAlignment="Center">

    <TextBlock Text="WPF QR Code Scanner" FontSize="20" FontWeight="Bold" Margin="0,0,0,16"/>

    <Button x:Name="ScanButton"
            Content="Select Image and Scan QR Code"
            Click="OnScanButtonClicked"
            Padding="12,8"
            Margin="0,0,0,16"
            HorizontalAlignment="Left"/>

    <TextBlock x:Name="ResultLabel"
               Text="Select an image to scan."
               TextWrapping="Wrap"
               FontSize="14"/>

</StackPanel>

<StackPanel Margin="28" VerticalAlignment="Center">

    <TextBlock Text="WPF QR Code Scanner" FontSize="20" FontWeight="Bold" Margin="0,0,0,16"/>

    <Button x:Name="ScanButton"
            Content="Select Image and Scan QR Code"
            Click="OnScanButtonClicked"
            Padding="12,8"
            Margin="0,0,0,16"
            HorizontalAlignment="Left"/>

    <TextBlock x:Name="ResultLabel"
               Text="Select an image to scan."
               TextWrapping="Wrap"
               FontSize="14"/>

</StackPanel>

XML

範例輸入

使用以下QR Code作為測試圖像。將其保存到您的裝置中，透過文件對話框選擇並點擊選擇圖像並掃描QR Code。解碼值應顯示為**https://ironsoftware.com**。

編碼 https://ironsoftware.com 的範例 QR 碼，用於測試 WPF QR 掃描器

範例QR Code — 編碼https://ironsoftware.com

使用IronQR掃描QR Code

當點擊按鈕時，OnScanButtonClicked打開文件對話框以選擇圖像。選擇的文件被載入至ResultLabel。

向OnScanButtonClicked方法：

using IronQr;
using IronSoftware.Drawing;
using Microsoft.Win32;
using System.Windows;

private void OnScanButtonClicked(object sender, RoutedEventArgs e)
{
    // Open a file dialog to select a QR code image
    var dialog = new OpenFileDialog
    {
        Title = "Select a QR code image",
        Filter = "Image Files|*.png;*.jpg;*.jpeg;*.bmp;*.gif;*.tiff"
    };

    if (dialog.ShowDialog() != true) return;

    var imageSource = dialog.FileName;

    // Load the image into IronQR
    var inputBmp = AnyBitmap.FromFile(imageSource);

    // Load the asset into QrImageInput
    QrImageInput imageInput = new QrImageInput(inputBmp);

    // Create a QR Reader object
    QrReader reader = new QrReader();

    // Read the input and get all embedded QR Codes
    IEnumerable<QrResult> results = reader.Read(imageInput);

    // Display the first result
    var firstResult = results.FirstOrDefault();
    ResultLabel.Text = firstResult != null
        ? "Scanned Text: " + firstResult.Value
        : "No QR code found in the selected image.";
}

using IronQr;
using IronSoftware.Drawing;
using Microsoft.Win32;
using System.Windows;

private void OnScanButtonClicked(object sender, RoutedEventArgs e)
{
    // Open a file dialog to select a QR code image
    var dialog = new OpenFileDialog
    {
        Title = "Select a QR code image",
        Filter = "Image Files|*.png;*.jpg;*.jpeg;*.bmp;*.gif;*.tiff"
    };

    if (dialog.ShowDialog() != true) return;

    var imageSource = dialog.FileName;

    // Load the image into IronQR
    var inputBmp = AnyBitmap.FromFile(imageSource);

    // Load the asset into QrImageInput
    QrImageInput imageInput = new QrImageInput(inputBmp);

    // Create a QR Reader object
    QrReader reader = new QrReader();

    // Read the input and get all embedded QR Codes
    IEnumerable<QrResult> results = reader.Read(imageInput);

    // Display the first result
    var firstResult = results.FirstOrDefault();
    ResultLabel.Text = firstResult != null
        ? "Scanned Text: " + firstResult.Value
        : "No QR code found in the selected image.";
}

Imports IronQr
Imports IronSoftware.Drawing
Imports Microsoft.Win32
Imports System.Windows

Private Sub OnScanButtonClicked(sender As Object, e As RoutedEventArgs)
    ' Open a file dialog to select a QR code image
    Dim dialog As New OpenFileDialog With {
        .Title = "Select a QR code image",
        .Filter = "Image Files|*.png;*.jpg;*.jpeg;*.bmp;*.gif;*.tiff"
    }

    If dialog.ShowDialog() <> True Then Return

    Dim imageSource As String = dialog.FileName

    ' Load the image into IronQR
    Dim inputBmp As AnyBitmap = AnyBitmap.FromFile(imageSource)

    ' Load the asset into QrImageInput
    Dim imageInput As New QrImageInput(inputBmp)

    ' Create a QR Reader object
    Dim reader As New QrReader()

    ' Read the input and get all embedded QR Codes
    Dim results As IEnumerable(Of QrResult) = reader.Read(imageInput)

    ' Display the first result
    Dim firstResult As QrResult = results.FirstOrDefault()
    ResultLabel.Text = If(firstResult IsNot Nothing, "Scanned Text: " & firstResult.Value, "No QR code found in the selected image.")
End Sub

Imports IronQr
Imports IronSoftware.Drawing
Imports Microsoft.Win32
Imports System.Windows

Private Sub OnScanButtonClicked(sender As Object, e As RoutedEventArgs)
    ' Open a file dialog to select a QR code image
    Dim dialog As New OpenFileDialog With {
        .Title = "Select a QR code image",
        .Filter = "Image Files|*.png;*.jpg;*.jpeg;*.bmp;*.gif;*.tiff"
    }

    If dialog.ShowDialog() <> True Then Return

    Dim imageSource As String = dialog.FileName

    ' Load the image into IronQR
    Dim inputBmp As AnyBitmap = AnyBitmap.FromFile(imageSource)

    ' Load the asset into QrImageInput
    Dim imageInput As New QrImageInput(inputBmp)

    ' Create a QR Reader object
    Dim reader As New QrReader()

    ' Read the input and get all embedded QR Codes
    Dim results As IEnumerable(Of QrResult) = reader.Read(imageInput)

    ' Display the first result
    Dim firstResult As QrResult = results.FirstOrDefault()
    ResultLabel.Text = If(firstResult IsNot Nothing, "Scanned Text: " & firstResult.Value, "No QR code found in the selected image.")
End Sub

OpenFileDialog提供原生的Windows文件選擇，過濾至常見圖像格式。 QrReader.Read返回每個檢測到的QR Code包含一個條目的IEnumerable<QrResult>。當找不到QR Code時，null，避免在沒有有效程式碼的圖像上產生例外。