1、修复同步旧核价到新核价报错问题

JLHHJSvr/Helper/MattressHelper.cs

@@ -3206,7 +3206,7 @@ namespace JLHHJSvr.Helper
             var outputFields = "mtrlid,name,if_subspecs,extra_cost";
             DbSqlHelper.SelectJoin(cmd, selectStr, ListEx.GetWhereStr(whereList), parms, "mtrlid", outputFields, 0,0, list);
 
-            if(extraList.Count > 0)
+            if(extraList != null && extraList.Count > 0)
             {
                 //
                 var namelist = list.Select(t => t.name).ToList();