1 files changed, 21 insertions, 0 deletions
diff --git a/src/DotNetOAuth/Messaging/MessagingUtilities.cs b/src/DotNetOAuth/Messaging/MessagingUtilities.cs
index 995fe66..8388051 100644
--- a/src/DotNetOAuth/Messaging/MessagingUtilities.cs
+++ b/src/DotNetOAuth/Messaging/MessagingUtilities.cs
@@ -154,6 +154,27 @@ namespace DotNetOAuth.Messaging {
 		}
 
 		/// <summary>
+		/// Strips any and all URI query parameters that start with some prefix.
+		/// </summary>
+		/// <param name="uri">The URI that may have a query with parameters to remove.</param>
+		/// <param name="prefix">The prefix for parameters to remove.</param>
+		/// <returns>Either a new Uri with the parameters removed if there were any to remove, or the same Uri instance if no parameters needed to be removed.</returns>
+		internal static Uri StripQueryArgumentsWithPrefix(this Uri uri, string prefix) {
+			NameValueCollection queryArgs = HttpUtility.ParseQueryString(uri.Query);
+			var matchingKeys = queryArgs.Keys.OfType<string>().Where(key => key.StartsWith(prefix, StringComparison.OrdinalIgnoreCase)).ToList();
+			if (matchingKeys.Count > 0) {
+				UriBuilder builder = new UriBuilder(uri);
+				foreach (string key in matchingKeys) {
+					queryArgs.Remove(key);
+				}
+				builder.Query = CreateQueryString(queryArgs.ToDictionary());
+				return builder.Uri;
+			} else {
+				return uri;
+			}
+		}
+
+		/// <summary>
 		/// Extracts the recipient from an HttpRequestInfo.
 		/// </summary>
 		/// <param name="request">The request to get recipient information from.</param>