单个sqlconnection中的多个sqltransactions

Question

我有一些要执行的代码，如下所示。但是在第二次迭代中，我不断收到异常“此SqlTransaction已完成；它不再可用”。有人可以帮我指出我在这里做错了吗？谢谢！

    SqlConnection cn = (SqlConnection)SqlConnectionManager.Instance.GetUserConnection(user);
 cn.Open();
 try
 {
    foreach (Master mRecord in masterList)
  {
   if (sqlTransaction == null)
       sqlTransaction = cn.BeginTransaction();
   SqlCommand cm = cn.CreateCommand();
   cm.Transaction = sqlTransaction;
   cm.CommandType = CommandType.StoredProcedure;
   cm.CommandText = "pr_InsertRecords";
       try
   {
    cm.ExecuteNonQuery();
    Debug.WriteLine("Auditor.Write: end sql table value param");
    sqlTransaction.Commit();
    sqlTransaction.Dispose();
   }
   catch (Exception Ex)
   {
    Debug.WriteLine(" Exception message: " + Ex.Message);
    if (Ex.InnerException != null)
    {
     Debug.WriteLine("Inner exception message" + Ex.InnerException.Message);
    }
    sqlTransaction.Rollback();
   }
  }
 }
 finally
 {
        cn.Close();
      }

Answer 1

在循环内，您可以提交或回滚，但不要将引用重置为null。SqlTransaction通常不按此方式使用using()，而是按原样使用SqlConnection：

using (SqlConnection cn = SqlConnectionManager.Instance.GetUserConnection(user)) 
{
  foreach (Master mRecord in masterList)
  {
  try
  {
    using (SqlTransaction sqlTransaction = cn.BeginTransaction()) 
    {
      using (SqlCommand cm = cn.CreateCommand()) 
      {
        cm.Transaction = sqlTransaction;
        cm.CommandType = CommandType.StoredProcedure;
        cm.CommandText = "pr_InsertRecords";
        cm.ExecuteNonQuery();
      }
      sqlTransaction.Commit();
      Debug.WriteLine("Auditor.Write: end sql table value param");
    }
  }
  catch (Exception Ex)
  {
    Debug.WriteLine(" Exception message: " + Ex.Message);
  }
}