优化发票删除功能

Src/Transforms/RestfulInvoice.Offset.Deficit.cs

@@ -210,22 +210,33 @@ namespace Kivii.Finances.Transforms
             if (invoices.Exists(o => o.OffsetKvid == Guid.Empty)) throw new Exception("存在未作废的发票,请先作废后再删除!");
             var offsets = conn.SelectByIds<Invoice>(invoices.ConvertAll(p => p.OffsetKvid));
 
-            var rtns = new RestfulUpdateResponse<Invoice>();
-            rtns.Results = new List<Invoice>();
-
-            var trans = conn.OpenTransaction();
-            try
+            var deletes = new List<Guid>();
+            if (!offsets.IsNullOrEmpty())
             {
                 foreach (var item in invoices)
                 {
-                    conn.DeleteById<Invoice>(item.Kvid);
-                    rtns.Results.Add(item);
+                    deletes.AddIfNotExists(item.Kvid);
+                }
             }
+            if (!offsets.IsNullOrEmpty())
+            {
                 foreach (var item in offsets)
                 {
-                    conn.DeleteById<Invoice>(item.Kvid);
-                    rtns.Results.Add(item);
+                    deletes.AddIfNotExists(item.Kvid);
                 }
+            }
+            var rtns = new RestfulDeleteResponse<Guid>();
+            rtns.Results = new List<Guid>();
+
+            var trans = conn.OpenTransaction();
+            try
+            {
+                foreach (var kvid in deletes)
+                {
+                    conn.DeleteById<Invoice>(kvid);
+                    rtns.Results.Add(kvid);
+                }
+                
                 trans.Commit();
             }
             catch (Exception ex)