捕捉到 System.InvalidOperationException
_HResult=-2146233079
_message=意外的连接状态。在使用包装提供程序时，请确保在已包装的 DbConnection 上实现 StateChange 事件。
HResult=-2146233079

解决参考：

https://stackoverflow.com/questions/4867602/entity-framework-there-is-already-an-open-datareader-associated-with-this-comma

https://stackoverflow.com/questions/20693216/there-is-already-an-open-datareader-associated-with-this-connection-which-must-b

EF There is already an open DataReader associated with this Command的更多相关文章

  1. There is already an open DataReader associated with this Command which must be closed first." exception in Entity Framework

    Fixing the "There is already an open DataReader associated with this Command which must be clos ...

  2. 在实体对象中访问导航属性里的属性值出现异常“There is already an open DataReader associated with this Command which must be closed first”

    在实体对象中访问导航属性里的属性值出现异常“There is already an open DataReader associated with this Command which must be ...

  3. 关于MultipleActiveResultSets属性导致的There is already an open DataReader associated with this Command which must be closed first的解决方法

    执行SqlDataReader.Read之后,如果还想用另一个SqlCommand执行Insert或者Update操作的话,会得到一个错误提示:There is already an open Dat ...

  4. C#.net mysql There is already an open datareader associated with this command引发的问题

    [参考]There is already an open datareader associated with this command引发的问题 我在语句中并未使用 DataReader,未何也提示 ...

  5. 多线程下，多次操作数据库报错，There is already an open DataReader associated with this Command which must be closed first.

    原文:https://www.cnblogs.com/sdusrz/p/4433108.html 执行SqlDataReader.Read之后,如果还想用另一个SqlCommand执行Insert或者 ...

  6. error 'there is already an open datareader associated with this command which must be closed first'

    This can be easily solved by allowing MARS in your connection string. Add MultipleActiveResultSets=t ...

  7. There is already an open DataReader associated with this Command which must be closed first

    通常出现在嵌套查询数据库(比如在一个qry的遍历时,又进行了数据库查询) 通过在连接字符串中允许MARS可以轻松解决这个问题. 将MultipleActiveResultSets = true添加到连 ...

  8. EF 常见异常总结

    问题:System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invoca ...

  9. EF core 性能调优

    Entity Framework Core performance tuning – a worked example Last Updated: February 25, 2019 | Create ...

随机推荐

  1. .NET工程师必须掌握的知识点

    Microsoft SQL Server 数据库 一.创建和维护数据库 1.数据库 SQL Server 数据库的组成部分?(参见联机丛书) 如何保证数据库的完整性.安全性.并发性? 数据库设计创建步 ...

  2. day1_jmeter接口测试

    一.Jmeter-http接口脚本: 步骤: 1.添加线程组 2.添加http请求 3.在http请求中写入接口url.路径.请求方式.参数 4.添加查看结果树 5.调用接口.查看返回值 二.Jmet ...

  3. 连连看java版

    主界面 import java.awt.BorderLayout; import java.awt.Color; import java.awt.Container; import java.awt. ...

  4. oracle中，将两个select语句的结果作为一个整体显示出来

    如果我们需要将两个select语句的结果作为一个整体显示出来,我们就需要用到union或者union all关键字.union(或称为联合)的作用是将多个结果合并在一起显示出来.union和union ...

  5. 【托业】托业（TOEIC）成绩 & 等级划分以及评分标准

    托业(TOEIC)成绩 & 等级划分以及评分标准 TOEIC全称:Test of English for International Communication(国际交流英语测评) 已通行全球 ...

  6. webmin账户重置密码

    locate changepass.pl(如果你不常使用locate的话那,先sudo updatedb)找到路径,在/usr/libexec/webmin/下面,转到这个目录下面./changepa ...

  7. django基础-01：软件框架，MVC框架，MVT

    1. 软件框架 一个公司是由公司中的各部部门来组成的,每一个部门拥有特定的职能,部门与部门之间通过相互的配合来完成让公司运转起来. 一个软件框架是由其中各个软件模块组成的,每一个模块都有特定的功能,模 ...

  8. MongoDB update修改器 目录

    MongoDB update修改器: 针对Fields的$修改器 $inc $set $unset MongoDB update修改器: 针对Arrays的$修改器 $push $pull $pop ...

  9. python创建有序字典及字典按照值的大小进行排序

    有序字典 在Python中,字典类型里面的元素默认是无序的,但是我们也可以通过collections模块创建有序字典 # -*- coding:utf-8 -*- # python有序字典需导入模块c ...

  10. LeetCode之有效括号

    class Solution:    def isValid(self,s):         #第一步,if 判断传入为空的情况        if s == "":      ...