fix

AutoTurnOver.Models/dc_report_profit_analysis.cs

@@ -352,9 +352,17 @@ namespace AutoTurnOver.Models
         /// 库存可用天数
         /// </summary>
         public int stock_available_days { get {
-                return  (int)Math.Ceiling((
-                    (quantity_purchase??0)+(quantity_transfer??0)+(usable_stock??0)+Math.Max(0, ocean_purchase)
-                    ) / forecast_daily_weighted_sales);
+                if (forecast_daily_weighted_sales <= 0)
+                {
+                    return 0;
+                }
+                else
+                {
+                    return (int)Math.Ceiling((
+                   (quantity_purchase ?? 0) + (quantity_transfer ?? 0) + (usable_stock ?? 0) + Math.Max(0, ocean_purchase)
+                   ) / forecast_daily_weighted_sales);
+                }
+               
             } }
 
         public DateTime stock_available_date { get