// 定时启动一个操作.任务 using System; using System.Collections.Generic; using System.Collections.ObjectModel; using System.ComponentModel; using System.Linq; using System.Text; using System.Threading; using System.Threading.Tasks; using System.Timers; /* 功能:定…
错误一: 程序完整报错: A second operation started on this context before a previous operation completed. This is usually caused by different threads using the same instance of DbContext, however instance members are not guaranteed to be thread safe. This could…