Add option Decodeonce : decodeOnce or decodeContinuously

Author: densen2014

Demo.Server/Pages/Index.razor

@@ -3,38 +3,54 @@
 
 <h3>BarcodeReader</h3>
 
-<h4>Barcode/QR code</h4>
+<h5>1D/2D barcode, QR code, Pdf417</h5>
 
 <button class="btn btn-primary"
         type="button"
         @onclick="(() => ShowScanBarcode = !ShowScanBarcode)">
     Scan
 </button>
 
+<br />
 Pdf417
 <input type="checkbox" @bind-value="Pdf417" />
+<br />
 
-<input type="text" class="form-control" style="min-width: 100px;"
-       @bind-value="BarCode"
-       placeholder="BarCode" />
+连续解码/DecodeContinuously
+<input type="checkbox" @bind-value="DecodeContinuously" />
+
+<br />
 
 @if (Pdf417)
 {
     <b>Pdf417:</b>
     <br />
     <pre>@BarCode</pre>
 }
+else if (DecodeContinuously)
+{
+    <b>DecodeContinuously:</b>
+    <br />
+    <pre>@BarCode</pre>
+}
+else
+{
+    <input type="text" class="form-control" style="min-width: 100px;"
+           @bind-value="BarCode"
+           placeholder="BarCode" />
+}
 
 @if (ShowScanBarcode)
 {
 
-    <BarcodeReader ScanResult="((e) => { BarCode=e; ShowScanBarcode = !ShowScanBarcode; })"
+    <BarcodeReader ScanResult="ScanResult"
                    ShowScanBarcode="ShowScanBarcode"
                    Close="(()=>ShowScanBarcode=!ShowScanBarcode)"
                    ScanBtnTitle="Scan"
                    ResetBtnTitle="Reset"
                    CloseBtnTitle="Close"
                    Pdf417="Pdf417"
+                   Decodeonce="!DecodeContinuously"
                    SelectDeviceBtnTitle="Select Device" />
 
 }
@@ -164,6 +180,11 @@ Pdf417
                         <td><div class="table-cell">false</div></td>
                         <td><div class="table-cell">Parameter</div></td>
                     </tr>
+                    <tr>
+                        <td><div class="table-cell">Decodeonce</div></td>
+                        <td><div class="table-cell">true</div></td>
+                        <td><div class="table-cell">Parameter</div></td>
+                    </tr>
                     <tr>
                         <td><div class="table-cell">SelectDeviceBtnTitle</div></td>
                         <td><div class="table-cell">Select device button title</div></td>
@@ -212,6 +233,7 @@ Pdf417
     public string? BarCode { get; set; }
 
     public bool Pdf417 { get; set; }
+    public bool DecodeContinuously { get; set; }
 
     private string message;
 
@@ -224,6 +246,19 @@ Pdf417
 
     bool ShowCodes;
 
+    private void ScanResult(string e)
+    {
+        if (!DecodeContinuously)
+        {
+            BarCode = e;
+            ShowScanBarcode = !ShowScanBarcode;
+        }
+        else
+        {
+            BarCode += e + Environment.NewLine;
+        }
+    }
+
     #region Custom
 
     /// <summary>

src/ZXingBlazor/Components/BarcodeReader.razor

@@ -99,6 +99,12 @@
     [Parameter]
     public bool Pdf417 { get; set; }
 
+    /// <summary>
+    /// 单次|连续解码,默认单次 / Decode Once or Decode Continuously, default is Once
+    /// </summary>
+    [Parameter]
+    public bool Decodeonce { get; set; } = true;
+
     /// <summary>
     /// 选项/ZXingOptions
     /// </summary>
@@ -123,9 +129,9 @@
             module = await JS.InvokeAsync<IJSObjectReference>("import", "./_content/ZXingBlazor/lib/zxing/zxingjs.js");
             if (options == null)
             {
-                options   = new ZXingOptions() { Pdf417= Pdf417 };
+                options   = new ZXingOptions() { Pdf417= Pdf417 , Decodeonce = Decodeonce };
             }
-            await module.InvokeVoidAsync("init", true, objRef, barcodeScannerElement, barcodeScannerElement.Id, options);
+            await module.InvokeVoidAsync("init", objRef, barcodeScannerElement, barcodeScannerElement.Id, options);
         }
         catch (Exception e)
         {

src/ZXingBlazor/Components/ZXingOptions.cs

@@ -14,7 +14,15 @@ namespace ZXingBlazor.Components;
 /// </summary>
 public class ZXingOptions
 {
-    public bool Pdf417 { get; set; }  
+    /// <summary>
+    /// decode only Pdf417 format
+    /// </summary>
+    public bool Pdf417 { get; set; }
+
+    /// <summary>
+    /// decodeOnce or decodeContinuously
+    /// </summary>
+    public bool Decodeonce { get; set; } = true;
 }
 
 

src/ZXingBlazor/ZXingBlazor.csproj

@@ -5,7 +5,7 @@
         <IsPackable>true</IsPackable>
         <ImplicitUsings>enable</ImplicitUsings>
         <PackageIcon>logo.png</PackageIcon>
-        <Version>0.2.4</Version>
+        <Version>0.2.5</Version>
         <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
         <Company>Densen Informatica</Company>
         <Authors>Alex Chow</Authors>

src/ZXingBlazor/wwwroot/lib/zxing/zxingjs.js

@@ -1,7 +1,8 @@
 import '/_content/ZXingBlazor/lib/zxing/zxing.min.js';
 var codeReader = null;
 var id = null;
-export function init(autostop, wrapper, element, elementid, options) {
+var supportsVibrate = false;
+export function init(wrapper, element, elementid, options) {
     console.log('init' + elementid);
     id = elementid;
     let selectedDeviceId;
@@ -10,6 +11,7 @@ export function init(autostop, wrapper, element, elementid, options) {
     let startButton = element.querySelector("[data-action=startButton]");
     let resetButton = element.querySelector("[data-action=resetButton]");
     let closeButton = element.querySelector("[data-action=closeButton]");
+    supportsVibrate = "vibrate" in navigator;
 
     console.log('init' + startButton.innerHTML);
     if (options.pdf417) {
@@ -42,36 +44,44 @@ export function init(autostop, wrapper, element, elementid, options) {
                 sourceSelectPanel.style.display = 'block'
             }
 
-            StartScan(autostop);
+            StartScan();
 
             startButton.addEventListener('click', () => {
                 StartScan();
             })
 
-            function StartScan(autostop) {
-                codeReader.decodeOnceFromVideoDevice(selectedDeviceId, 'video').then((result) => {
-                    console.log(result)
-                    
-                    var supportsVibrate = "vibrate" in navigator;
-                    if (supportsVibrate) navigator.vibrate(1000);
-
-                    if (autostop) {
+            function StartScan() {
+                if (options.decodeonce) {
+                    codeReader.decodeOnceFromVideoDevice(selectedDeviceId, 'video').then((result) => {
+                        console.log(result)
+                        if (supportsVibrate) navigator.vibrate(1000);                        
                         console.log('autostop');
                         codeReader.reset();
                         return wrapper.invokeMethodAsync("GetResult", result.text);
-                    } else {
-                        console.log('None-stop');
-                        codeReader.reset();
-                        wrapper.invokeMethodAsync("GetResult", result.text);
-                    }
+                    }).catch((err) => {
+                        if (err && !(err instanceof ZXing.NotFoundException)) {
+                            console.log(err)
+                            wrapper.invokeMethodAsync("GetError", err + '');
+                        }
+                    })
+                } else {
+                    codeReader.decodeFromVideoDevice(selectedDeviceId, 'video', (result, err) => {
+                        if (result) {
+                            console.log(result)
+                            if (supportsVibrate) navigator.vibrate(1000);
+                            console.log('None-stop');
+                            wrapper.invokeMethodAsync("GetResult", result.text);
+                        }
+                        if (err && !(err instanceof ZXing.NotFoundException)) {
+                            console.log(err)
+                            wrapper.invokeMethodAsync("GetError", err + '');
+                        }
+                    })
+                }
 
-                }).catch((err) => {
-                    if (err && !(err instanceof ZXing.NotFoundException)) {
-                        console.log(err)
-                        wrapper.invokeMethodAsync("GetError", err + '');
-                    }
-                })
-                console.log(`Started continous decode from camera with id ${selectedDeviceId}`)
+                var x = `decodeContinuously`;
+                if (options.decodeonce) x = `decodeOnce`;
+                console.log(`Started ` + x +` decode from camera with id ${selectedDeviceId}`)
             }
 
             resetButton.addEventListener('click', () => {