调整GetSampleTimeFromLastUpdate精度算法

HealthMonitor.WebApi/Worker.cs

@@ -2633,20 +2633,32 @@ namespace HealthMonitor.WebApi
             //}
         }
 
-        private DateTime GetSampleTimeFromLastUpdate(DateTime lastUpdate,int interval)
+        //private DateTime GetSampleTimeFromLastUpdate(DateTime lastUpdate,int interval)
+        //{
+        //    DateTime nowInterval = lastUpdate;
+        //    //if (nowInterval.Second > 0)
+        //    //{
+        //    //    nowInterval = nowInterval.AddMinutes(1);
+        //    //}
+        //    // 计算last_update到上一间隔的分钟数
+        //    int minutesToSubtract = nowInterval.Minute % interval;
+
+        //    // 计算上一间隔的时间
+        //    DateTime previousInterval = nowInterval.AddMinutes(-minutesToSubtract).AddSeconds(-nowInterval.Second).AddMilliseconds(-nowInterval.Millisecond);
+
+        //    return previousInterval;
+        //}
+
+        public static DateTime GetSampleTimeFromLastUpdate(DateTime lastUpdate, int interval)
         {
-            DateTime nowInterval = lastUpdate;
-            //if (nowInterval.Second > 0)
-            //{
-            //    nowInterval = nowInterval.AddMinutes(1);
-            //}
-            // 计算last_update到上一间隔的分钟数
-            int minutesToSubtract = nowInterval.Minute % interval;
+            // 获取当前的分钟
+            int minute = lastUpdate.Minute;
 
-            // 计算上一间隔的时间
-            DateTime previousInterval = nowInterval.AddMinutes(-minutesToSubtract).AddSeconds(-nowInterval.Second).AddMilliseconds(-nowInterval.Millisecond);
+            // 按 15 分钟为单位划分时间段
+            int intervalStartMinute = (minute / interval) * interval;
 
-            return previousInterval;
+            // 返回当前时间刻度下的 DateTime，保留小时和新计算的分钟，秒和毫秒设为0
+            return new DateTime(lastUpdate.Year, lastUpdate.Month, lastUpdate.Day, lastUpdate.Hour, intervalStartMinute, 0, 0);
         }
     }
 }