WPF ZoomIn/Out Functionality

CefSharp.Core/ManagedCefBrowserAdapter.h

@@ -282,6 +282,28 @@ namespace CefSharp
             }
         }
 
+        double GetZoomLevel()
+        {
+            auto cefHost = _renderClientAdapter->TryGetCefHost();
+
+            if (cefHost != nullptr)
+            {
+                return cefHost->GetZoomLevel();
+            }
+
+            return 0;
+        }
+
+        void SetZoomLevel(double zoomLevel)
+        {
+            auto cefHost = _renderClientAdapter->TryGetCefHost();
+
+            if (cefHost != nullptr)
+            {
+                cefHost->SetZoomLevel(zoomLevel);
+            }
+        }
+
         virtual void Error( Exception^ ex )
         {
 

CefSharp.Wpf.Example/Views/Main/MainView.xaml

@@ -191,6 +191,13 @@
                             <MenuItem Header="Forward"
                                       Command="{Binding WebBrowser.ForwardCommand}" />
                             <Separator />
+                            <MenuItem Header="Zoom In"
+                                      Command="{Binding WebBrowser.ZoomInCommand}" />
+                            <MenuItem Header="Zoom Out"
+                                      Command="{Binding WebBrowser.ZoomOutCommand}" />
+                            <MenuItem Header="Zoom Reset"
+                                      Command="{Binding WebBrowser.ZoomResetCommand}" />
+                            <Separator />
                             <MenuItem Header="View Source"
                                       Command="{Binding ViewSourceCommand}" />
                         </ContextMenu>

CefSharp.Wpf/IWpfWebBrowser.cs

@@ -1,5 +1,4 @@
-using System.ComponentModel;
-using System.Windows.Input;
+using System.Windows.Input;
 
 namespace CefSharp.Wpf
 {
@@ -43,6 +42,21 @@ public interface IWpfWebBrowser : IWebBrowser
         /// </summary>
         ICommand ReloadCommand { get; }
 
+        /// <summary>
+        /// Command which increases the zoom level
+        /// </summary>
+        ICommand ZoomInCommand { get; }
+
+        /// <summary>
+        /// Command which decreases the zoom level
+        /// </summary>
+        ICommand ZoomOutCommand { get; }
+
+        /// <summary>
+        /// Command which resets the zoom level to default
+        /// </summary>
+        ICommand ZoomResetCommand { get; }
+
         /// <summary>
         /// Opens up a new program window (using the default text editor) where the source code of the currently displayed web
         /// page is shown.
@@ -55,5 +69,11 @@ public interface IWpfWebBrowser : IWebBrowser
         /// <returns><c>true</c> if keyboard focus and logical focus were set to this element; <c>false</c> if only logical focus
         /// was set to this element, or if the call to this method did not force the focus to change.</returns>
         bool Focus();
+
+        /// <summary>
+        /// The zoom level at which the browser control is currently displaying. Can be set to 0 to clear the zoom level(resets to default zoom level)
+        /// </summary>
+        /// <remarks>This property is a Dependency Property and fully supports data binding.</remarks>
+        double ZoomLevel { get; set; }
     }
 }

CefSharp.Wpf/WebView.cs

@@ -47,6 +47,9 @@ public class WebView : ContentControl, IRenderWebBrowser, IWpfWebBrowser
         public ICommand BackCommand { get; private set; }
         public ICommand ForwardCommand { get; private set; }
         public ICommand ReloadCommand { get; private set; }
+        public ICommand ZoomInCommand { get; private set; }
+        public ICommand ZoomOutCommand { get; private set; }
+        public ICommand ZoomResetCommand { get; private set; }
 
         public bool CanGoBack { get; private set; }
         public bool CanGoForward { get; private set; }
@@ -144,7 +147,61 @@ public string Title
         public static readonly DependencyProperty TitleProperty =
             DependencyProperty.Register("Title", typeof(string), typeof(WebView), new PropertyMetadata(defaultValue: null));
 
-        #endregion CleanupElement dependency property
+        #endregion Title dependency property
+
+        #region ZoomLevel dependency property
+
+        /// <summary>
+        /// The zoom level at which the browser control is currently displaying. Can be set to 0 to clear the zoom level(resets to default zoom level)
+        /// </summary>
+        /// <remarks>This property is a Dependency Property and fully supports data binding.</remarks>
+        public double ZoomLevel
+        {
+            get { return (double)GetValue(ZoomLevelProperty); }
+            set { SetValue(ZoomLevelProperty, value); }
+        }
+
+        public static readonly DependencyProperty ZoomLevelProperty =
+            DependencyProperty.Register("ZoomLevel", typeof(double), typeof(WebView),
+                                        new UIPropertyMetadata(0d, OnZoomLevelChanged));
+
+        private static void OnZoomLevelChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
+        {
+            var owner = (WebView)sender;
+            var oldValue = (double)args.OldValue;
+            var newValue = (double)args.NewValue;
+
+            owner.OnZoomLevelChanged(oldValue, newValue);
+        }
+
+        protected virtual void OnZoomLevelChanged(double oldValue, double newValue)
+        {
+            if (!Cef.IsInitialized)
+            {
+                throw new InvalidOperationException("Cef::IsInitialized is false");
+            }
+
+            managedCefBrowserAdapter.SetZoomLevel(newValue);
+        }
+
+        #endregion ZoomLevel dependency property
+
+        #region ZoomLevelIncrement dependency property
+
+        /// <summary>
+        /// Specifies the amount used to increase/decrease to ZoomLevel by
+        /// By Default this value is 0.10
+        /// </summary>
+        public double ZoomLevelIncrement
+        {
+            get { return (double)GetValue(ZoomLevelIncrementProperty); }
+            set { SetValue(ZoomLevelIncrementProperty, value); }
+        }
+
+        public static readonly DependencyProperty ZoomLevelIncrementProperty =
+            DependencyProperty.Register("ZoomLevelIncrement", typeof(double), typeof(WebView), new PropertyMetadata(0.10));
+
+        #endregion ZoomLevelIncrement dependency property
 
         #region CleanupElement dependency property
 
@@ -203,7 +260,7 @@ protected virtual void Cleanup()
             }
         }
 
-        #endregion Title dependency property
+        #endregion CleanupElement dependency property
 
         #region TooltipText dependency property
 
@@ -275,6 +332,9 @@ public WebView()
             BackCommand = new DelegateCommand(Back, () => CanGoBack);
             ForwardCommand = new DelegateCommand(Forward, () => CanGoForward);
             ReloadCommand = new DelegateCommand(Reload, () => CanReload);
+            ZoomInCommand = new DelegateCommand(ZoomIn);
+            ZoomOutCommand = new DelegateCommand(ZoomOut);
+            ZoomResetCommand = new DelegateCommand(ZoomReset);
 
             managedCefBrowserAdapter = new ManagedCefBrowserAdapter(this);
             managedCefBrowserAdapter.CreateOffscreenBrowser(BrowserSettings ?? new BrowserSettings());
@@ -748,6 +808,30 @@ public void Reload()
             managedCefBrowserAdapter.Reload();
         }
 
+        private void ZoomIn()
+        {
+            DoInUi(() =>
+            {
+                ZoomLevel = ZoomLevel + ZoomLevelIncrement;
+            });
+        }
+
+        private void ZoomOut()
+        {
+            DoInUi(() =>
+            {
+                ZoomLevel = ZoomLevel - ZoomLevelIncrement;
+            });
+        }
+
+        private void ZoomReset()
+        {
+            DoInUi(() =>
+            {
+                ZoomLevel = 0;
+            });
+        }
+
         public void ShowDevTools()
         {
             // TODO: Do something about this one.