Requested changes

src/Avalonia.Visuals/Media/FontFamily.cs

@@ -79,9 +79,23 @@ namespace Avalonia.Media
         /// </returns>
         public override string ToString()
         {
+            if (Key != null)
+            {
+                return Key + "#" + Name;
+            }
+
             return Name;
         }
 
+        /// <summary>
+        /// Implicit conversion of FontFamily to string
+        /// </summary>
+        /// <param name="fontFamily"></param>
+        public static implicit operator string(FontFamily fontFamily)
+        {
+            return fontFamily.ToString();
+        }
+
         /// <summary>
         /// Parses a <see cref="T:Avalonia.Media.FontFamily"/> string.
         /// </summary>

src/Avalonia.Visuals/Media/Fonts/FontFamilyKey.cs

@@ -88,12 +88,13 @@ namespace Avalonia.Media.Fonts
         /// </returns>
         public override string ToString()
         {
-            if (FileName != null)
-            {
-                return Location.AbsolutePath + "." + FileName;
-            }
+            if (FileName == null) return Location.PathAndQuery;
+
+            var builder = new UriBuilder(Location);
+
+            builder.Path += "." + FileName;
 
-            return Location.AbsolutePath;
+            return builder.ToString();
         }
     }
 }

src/Avalonia.Visuals/Media/Typeface.cs

@@ -7,6 +7,13 @@ namespace Avalonia.Media
     /// </summary>
     public class Typeface
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Typeface"/> class.
+        /// </summary>
+        /// <param name="fontFamily">The font family.</param>
+        /// <param name="fontSize">The font size, in DIPs.</param>
+        /// <param name="style">The font style.</param>
+        /// <param name="weight">The font weight.</param>
         public Typeface(FontFamily fontFamily, double fontSize = 12, FontStyle style = FontStyle.Normal,
         FontWeight weight = FontWeight.Normal)
         {

src/Shared/PlatformSupport/AssetLoader.cs

@@ -216,5 +216,5 @@ namespace Avalonia.Shared.PlatformSupport
             public Dictionary<string, IAssetDescriptor> Resources { get; }
             public string Name { get; }
         }
-    }  
+    }
 }

src/Windows/Avalonia.Direct2D1/Direct2D1Platform.cs

@@ -117,7 +117,7 @@ namespace Avalonia.Direct2D1
         }
 
         public IFormattedTextImpl CreateFormattedText(
-            string text,           
+            string text,
             Typeface typeface,
             TextAlignment textAlignment,
             TextWrapping wrapping,

tests/Avalonia.Visuals.UnitTests/Media/FontFamilyTests.cs

@@ -24,6 +24,14 @@ namespace Avalonia.Visuals.UnitTests.Media
             Assert.Throws<ArgumentNullException>(() => new FontFamily((IEnumerable<string>)null));
         }
 
+        [Fact]
+        public void ShouldImplicitlyConvertToString()
+        {
+            var fontFamily = new FontFamily("Arial");        
+
+            Assert.Equal("Arial", fontFamily);
+        }
+
         [Fact]
         public void Parse_Parses_FontFamily_With_Name()
         {