diff --git a/src/PhotoCollector/PhotoCollector.csproj b/src/PhotoCollector/PhotoCollector.csproj
index b2146c1..2437476 100644
--- a/src/PhotoCollector/PhotoCollector.csproj
+++ b/src/PhotoCollector/PhotoCollector.csproj
@@ -10,7 +10,7 @@
     <DebugType>full</DebugType>
     <AllowUnsafeBlocks>True</AllowUnsafeBlocks>
 	<SatelliteResourceLanguages>zh-Hans</SatelliteResourceLanguages>
-	<Version>0.1.0</Version>
+	<Version>0.1.1</Version>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
diff --git a/src/PhotoCollector/WebView2Interop.cs b/src/PhotoCollector/WebView2Interop.cs
index 3f2ae2e..9703da9 100644
--- a/src/PhotoCollector/WebView2Interop.cs
+++ b/src/PhotoCollector/WebView2Interop.cs
@@ -15,5 +15,10 @@ namespace PhotoCollector
             }
             return null;
         }
+
+        public string GetAppPath()
+        {
+            return AppContext.BaseDirectory;
+        }
     }
 }
\ No newline at end of file
diff --git a/src/WebApiTestServer/wwwroot/index.html b/src/WebApiTestServer/wwwroot/index.html
index 624e045..04b26a2 100644
--- a/src/WebApiTestServer/wwwroot/index.html
+++ b/src/WebApiTestServer/wwwroot/index.html
@@ -86,7 +86,7 @@
     <hr />
     <img id="idCard" width="102" height="126" alt="" />
     <script>
-        var appBasePath = navigator.userAgent.split('|')[1];
+        var appBasePath = window.chrome.webview.hostObjects.sync.dotnet.GetAppPath();
         //window.chrome.webview.postMessage({ command: "setStatus", message: `start at ${appBasePath}` });
 
         function onIdCardRead(card) {
@@ -213,30 +213,33 @@
             var context = canvas.getContext('2d');
             context.drawImage(video, (video.width - width) / 2, (video.height - height) / 2, width, height, 0, 0, width, height);
         };
-        function init() {
-            select.onchange = function (event) {
-                var hdConstraints = {
-                    audio: false,
-                    video: {
-                        width: { min: 640, ideal: 1280, max: 1920 },
-                        height: { min: 360, ideal: 720, max: 1080 },
-                        deviceId: event.target.value
-                    }
-                };
-                navigator.mediaDevices.getUserMedia(hdConstraints).then(function (mediaStream) {
-                    video.srcObject = mediaStream;
-                    video.addEventListener("loadedmetadata", function (e) {
-                        video.width = e.srcElement.videoWidth;
-                        video.height = e.srcElement.videoHeight;
-                        //var wrapper = document.querySelector('.videoWrapper');
-                        //wrapper.style.width = video.width + 'px';
-                        //wrapper.style.height = video.height + 'px';
-                        video.play();
-                    });
-                }, function (err) {
-                    console.error('getUserMediaErrorCallback')
-                });
+        select.onchange = function (event) {
+            var hdConstraints = {
+                audio: false,
+                video: {
+                    width: { min: 640, ideal: 1280, max: 1920 },
+                    height: { min: 360, ideal: 720, max: 1080 },
+                    deviceId: event.target.value
+                }
             };
+            navigator.mediaDevices.getUserMedia(hdConstraints).then(function (mediaStream) {
+                video.srcObject = mediaStream;
+                video.addEventListener("loadedmetadata", function (e) {
+                    video.width = e.srcElement.videoWidth;
+                    video.height = e.srcElement.videoHeight;
+                    //var wrapper = document.querySelector('.videoWrapper');
+                    //wrapper.style.width = video.width + 'px';
+                    //wrapper.style.height = video.height + 'px';
+                    video.play();
+                });
+            }, function (err) {
+                console.error('getUserMediaErrorCallback')
+            });
+        };
+        function init() {
+            if (video.srcObject&&video.srcObject.active) {
+                return;
+            }
             navigator.mediaDevices.enumerateDevices()
                 .then(function (devices) {
                     select.innerHTML = "";
@@ -255,7 +258,8 @@
                     console.log(err.name + ": " + err.message);
                 });
         }
-        init();
+        setInterval(init, 5000);
+        //init();
     </script>
 </body>
 </html>
\ No newline at end of file