Fixes #304, UrlPath.IsAbsoluteUrl method was misidentifying the URL a…

…s absolute when an absolute URL was added as a query string parameter, as in the case with ASP.NET error pages.

src/MvcSiteMapProvider/MvcSiteMapProvider.Tests/Unit/Web/UrlPathTest.cs

@@ -89,6 +89,21 @@ public void IsAbsoluteUrl_WithAbsoluteUrl_ShouldReturnTrue()
             Assert.AreEqual(expected, actual);
         }
 
+        [Test]
+        public void IsAbsoluteUrl_WithAbsoluteUrlAsQueryParameter_ShouldReturnFalse()
+        {
+            // arrange
+            var target = this.NewUrlPath();
+
+            // act
+            var result = target.IsAbsoluteUrl(@"/error/pagenotfound?404;http://somewhere.com/directory/subdirectory/page.aspx?a=b");
+
+            // assert
+            var actual = result;
+            var expected = false;
+            Assert.AreEqual(expected, actual);
+        }
+
         /// <summary>
         /// Return false when the virtual application name (and host name) match.
         /// </summary>

src/MvcSiteMapProvider/MvcSiteMapProvider/Web/UrlPath.cs

@@ -4,6 +4,7 @@
 using System.Globalization;
 using System.Linq;
 using System.Text;
+using System.Text.RegularExpressions;
 using System.Web;
 using MvcSiteMapProvider.Web.Mvc;
 
@@ -363,8 +364,14 @@ public string UrlDecode(string url)
         /// <returns><b>true</b> if the URL is absolute; otherwise <b>false</b>.</returns>
         public bool IsAbsoluteUrl(string url)
         {
-            // There must be at least 1 character before the scheme delimiter.
-            return (url.IndexOf(Uri.SchemeDelimiter) > 0);
+            // Optimization: Return false early if there is no scheme delimiter in the string
+            // prefixed by at least 1 character.
+            if (!(url.IndexOf(Uri.SchemeDelimiter) > 0))
+                return false;
+
+            // There must be at least 1 word character before the scheme delimiter.
+            // This ensures we don't return true for query strings that contain absolute URLs.
+            return Regex.IsMatch(url, @"^\w+://", RegexOptions.Compiled);
         }
 
         /// <summary>