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Back/Data/Models/InvoiceItem.cs

@@ -25,12 +25,12 @@ namespace  Back.Data.Models
         public string? mu { get { return cODItem != null ? cODItem.CODUnit.UnitTaxID : null; } }
         //میزان ارز
         [MaxLength(18)]
-        public decimal? cfee { get { return fee / exr; } }
+        public decimal? cfee { get { return exr==null || exr==0 ? null : fee / exr; } }
         //مبلغ مالیات بر ارزش افزوده
         [MaxLength(18)]
         public decimal? vam { get 
             {
-                return invoice?.pattern?.inp == 9 ? fee*vra/100 :
+                return vra==0 ? 0 : invoice?.pattern?.inp == 9 ? fee*vra/100 :
                      invoice?.pattern?.inp == 13 ? ((tcpbs+9)/100)+((prdis*vra)/100)
                     : vra * adis / 100; 
             } }