diff --git a/Elight.Utility/Extensions/ConvertorHelper.cs b/Elight.Utility/Extensions/ConvertorHelper.cs
index 8bb0c5a..05f3c49 100644
--- a/Elight.Utility/Extensions/ConvertorHelper.cs
+++ b/Elight.Utility/Extensions/ConvertorHelper.cs
@@ -140,6 +140,61 @@ namespace Elight.Utility.Extensions
             DateTime dtResult = dtStart.Add(toNow);
             return dtResult;
         }
-        
+
+    }
+
+    public static class DateHelper
+    {
+        public static DateTime GetStartDateOfDay(DateTime date)
+        {
+            return date.Date;
+        }
+        public static DateTime GetEndDateOfDay(DateTime date)
+        {
+            return date.Date.AddDays(1).AddSeconds(-1);
+        }
+        public static DateTime GetStartDateOfMonth(DateTime date)
+        {
+            return date.AddDays(1 - date.Day).Date;
+        }
+        public static DateTime GetEndDateOfMonth(DateTime date)
+        {
+            return GetStartDateOfMonth(date).AddMonths(1).AddSeconds(-1);
+        }
+        public static DateTime GetStartDateOfYear(DateTime date)
+        {
+            return date.AddDays(1 - date.Day).AddMonths(1 - date.Month).Date;
+        }
+        public static DateTime GetEndDateOfYear(DateTime date)
+        {
+            return GetStartDateOfYear(date).AddYears(1).AddSeconds(-1);
+        }
+        public static List<DateTime> GetArrayByDay(DateTime starttime, DateTime endtime)
+        {
+            var list = new List<DateTime>();
+            for (DateTime dt = starttime; dt.Date <= endtime.Date; dt = dt.AddDays(1))
+            {
+                list.Add(dt.Date);
+            }
+            return list;
+        }
+        public static List<DateTime> GetArrayByMonth(DateTime starttime, DateTime endtime)
+        {
+            var list = new List<DateTime>();
+            for (DateTime dt = starttime; dt.Date <= endtime.Date; dt = dt.AddMonths(1))
+            {
+                list.Add(GetStartDateOfMonth(dt.Date));
+            }
+            return list;
+        }
+        public static List<DateTime> GetArrayByYear(DateTime starttime, DateTime endtime)
+        {
+            var list = new List<DateTime>();
+            for (DateTime dt = starttime; dt.Date <= endtime.Date; dt = dt.AddYears(1))
+            {
+                list.Add(GetStartDateOfYear(dt.Date));
+            }
+            return list;
+        }
     }
 }