close #253

src/Shared/HandyControl_Shared/Collections/DateTimeRangeComparer.cs

@@ -0,0 +1,15 @@
+using System.Collections.Generic;
+using HandyControl.Data;
+
+namespace HandyControl.Collections
+{
+    public class DateTimeRangeComparer : IComparer<DateTimeRange>
+    {
+        public int Compare(DateTimeRange x, DateTimeRange y)
+        {
+            if (x.Start > y.Start && x.End > y.End) return 1;
+            if (x.Start < y.Start && x.End < y.End) return -1;
+            return 0;
+        }
+    }
+}