修复 在SQLite 使用 using (SQLiteTransaction tran = connection.BeginTransaction())，解决tran释放问题

Project.SQLiteHelper/SQLiteHelper/SQLiteHelper.cs

@@ -491,9 +491,9 @@ namespace SQLite
         /// <returns></returns>
         public bool QueryTran(IEnumerable<string> queryList)
         {
-            if (isHoldQueryTran)
+            if (isHoldQueryTran)//打包模式
             {
-                holdQueryList.AddRange(queryList);
+                holdQueryList.AddRange(queryList);//记录SQLs
                 return true;
             }
             else
@@ -504,7 +504,8 @@ namespace SQLite
                     {
                         connection.Open();
 
-                        SQLiteTransaction tran = connection.BeginTransaction();
+                        using (SQLiteTransaction tran = connection.BeginTransaction())
+                        {
                             bool check = false;
                             try
                             {
@@ -513,24 +514,22 @@ namespace SQLite
                                     command.CommandText = item;
                                     command.ExecuteNonQuery();
                                 }
-                            tran.Commit();
-                            check = true;
+                                tran.Commit();//事务提交
+                                check = true;//执行成功
                             }
                             catch (Exception ex)
                             {
-                            tran.Rollback();
-                            check = false;
+                                //异常
+                                tran.Rollback();//事务回滚
+                                check = false;//执行失败
                                 logger.Error(ex, Newtonsoft.Json.JsonConvert.SerializeObject(queryList));
-                            throw ex;
-                        }
-                        finally
-                        {
-                            connection.Close();
+                                throw ex;//抛出异常
                             }
                             return check;
                         }
                     }
                 }
+            }
 
         }
 
@@ -564,35 +563,36 @@ namespace SQLite
                     {
                         connection.Open();
 
-                        SQLiteTransaction tran = connection.BeginTransaction();
-                        bool check = false;
+                        using (SQLiteTransaction tran = connection.BeginTransaction())
+                        {
+                            bool check;
                             try
                             {
-                            foreach (string item in holdQueryList)
+                                foreach (string item in holdQueryList)//全部SQL 打包为一个事务执行
                                 {
                                     command.CommandText = item;
                                     command.ExecuteNonQuery();
                                 }
-                            tran.Commit();
-                            check = true;
+                                tran.Commit();//事务提交
+                                check = true;//执行成功
                             }
                             catch (Exception ex)
                             {
-                            tran.Rollback();
-                            check = false;
-                            throw ex;
+                                tran.Rollback();//异常出错，事务回滚
+                                check = false;//执行失败
+                                throw ex;//弹出异常
                             }
                             finally
                             {
-                            holdQueryList.Clear();
-                            connection.Close();
-                            isHoldQueryTran = false;
+                                holdQueryList.Clear();//清除 SQL
+                                isHoldQueryTran = false;//退出打包模式
                             }
                             return check;
                         }
                     }
                 }
-            isHoldQueryTran = false;
+            }
+            isHoldQueryTran = false;//退出打包模式
             return true;
         }
         /// <summary>