Issue 225 - Image with large embedded image fails to render

- Changed SvgImage.Href property from Uri type to String to avoid UriFormatException if Uri contains too much data
- Changed GetImage to receive a string instead of Uri object.
  - Created a temp Uri object in method with substring of allowed length and using this to determine Uri characteristics

Source/Basic Shapes/SvgImage.cs

@@ -74,9 +74,9 @@ namespace Svg
 		}
 
 		[SvgAttribute("href", SvgAttributeAttribute.XLinkNamespace)]
-		public virtual Uri Href
+		public virtual string Href
 		{
-			get { return this.Attributes.GetAttribute<Uri>("href"); }
+			get { return this.Attributes.GetAttribute<string>("href"); }
 			set { this.Attributes["href"] = value; }
 		}
 
@@ -232,14 +232,15 @@ namespace Svg
             }
         }
 
-        protected object GetImage(Uri uri)
+        protected object GetImage(string uriString)
         {
             try
             {
+                var uri = new Uri(uriString.Substring(0, 65519)); //Uri MaxLength is 65519 (https://msdn.microsoft.com/en-us/library/z6c2z492.aspx)
+
                 // handle data/uri embedded images (http://en.wikipedia.org/wiki/Data_URI_scheme)
                 if (uri.IsAbsoluteUri && uri.Scheme == "data")
                 {
-                    string uriString = uri.OriginalString;
                     int dataIdx = uriString.IndexOf(",") + 1;
                     if (dataIdx <= 0 || dataIdx + 1 > uriString.Length)
                         throw new Exception("Invalid data URI");
@@ -284,7 +285,7 @@ namespace Svg
             }
             catch (Exception ex)
             {
-                Trace.TraceError("Error loading image: '{0}', error: {1} ", uri, ex.Message);
+                Trace.TraceError("Error loading image: '{0}', error: {1} ", uriString, ex.Message);
                 return null;
             }
         }

Tests/Svg.UnitTests/LargeEmbeddedImageTest.cs

+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Svg.DataTypes;
+using System;
+using System.Diagnostics;
+using System.Drawing;
+using System.IO;
+
+namespace Svg.UnitTests
+{
+
+    /// <summary>
+    /// Test Class of rendering SVGs with a large embedded image
+    /// Based on Issue 225
+    /// </summary>
+    /// <remarks>
+    /// Test use the following embedded resources:
+    ///   - Issue225_LargeUri\Speedometer.svg
+    /// </remarks>
+    [TestClass]
+    public class LargeEmbeddedImageTest : SvgTestHelper
+    {
+        protected override string TestResource { get { return GetFullResourceString("Issue225_LargeUri.Speedometer.svg"); } }
+        protected override int ExpectedSize { get { return 160000; } } 
+
+        [TestMethod]
+        public void TestImageIsRendered()
+        {
+            LoadSvg(GetXMLDocFromResource());
+        }
+    }
+}

Tests/Svg.UnitTests/Svg.UnitTests.csproj

@@ -55,6 +55,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="CssQueryTest.cs" />
+    <Compile Include="LargeEmbeddedImageTest.cs" />
     <Compile Include="MarkerEndTest.cs" />
     <Compile Include="MetafileRenderingTest.cs" />
     <Compile Include="MultiThreadingTest.cs" />
@@ -81,6 +82,9 @@
   <ItemGroup>
     <EmbeddedResource Include="Resources\Issue212_MakerEnd\OperatingPlan.svg" />
   </ItemGroup>
+  <ItemGroup>
+    <EmbeddedResource Include="Resources\Issue225_LargeUri\Speedometer.svg" />
+  </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.