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添加到连接字符串的提供程序部分

    "SqlServerConnection": "Server=.\\sqlexpress;Database=test;Integrated Security=True;Connect Timeout=15;MultipleActiveResultSets=true",

　　

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

  5. 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 ...

  6. There is already an open DataReader associated with this Connection which must be closed first

    使用MVC4 EF Linq获取foreach列表循环的时候遇到了如下的问题:报错提示 There is already an open DataReader associated with this ...

  7. 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 ...

  8. EF There is already an open DataReader associated with this Command

    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 DbCon ...

  9. There is already an open DataReader associated with this Connection which must be closed first EF

    废话不多说,直接 上图,及解决办法.不过问题还不是太清楚到底为什么会出现这个情况..........  

随机推荐

  1. ubuntu自定义截图截图

    如果只需要获取一张屏幕截图,不对其进行编辑的话,那么键盘的默认快捷键就可以满足要求了.而且不仅仅是 Ubuntu ,绝大部分的 Linux 发行版和桌面环境都支持以下这些快捷键: PrtSc – 获取 ...

  2. leetcode203. 移除链表元素

    方法一(删除头结点时另做考虑) class Solution { public: ListNode* removeElements(ListNode* head, int val) { if(head ...

  3. spring cloud fegin传递request header

    本文链接:https://blog.csdn.net/zhongzunfa/article/details/82791903 1.概述 今天一个朋友, 遇到一个如何在使用spring cloud fe ...

  4. Codeforces Round 573 (Div.1) 题解

    这场怎么说呢……有喜有悲吧. 开场先秒了 A.看到 B,感觉有点意思,WA 了 2 发后也过了. 此时还在 rk 前 200. 开 C,一看就不可做.跟榜,切 D 人数是 C 的两倍. 开 D.一眼感 ...

  5. Qt Quick 布局介绍

    在 Qt Quick 中有两套与布局管理相关的类库,一套叫作 Item Positioner(定位器),一套叫作 Item Layout(布局). 定位器包括 Row(行定位器).Column(列定位 ...

  6. Eclipse JAX-RS (REST Web Services) 2.0 requires Java 1.6 or newer

    pom.xml文件中添加: <build> <plugins> <plugin> <groupId>org.apache.maven.plugins&l ...

  7. golang net之http server

    golang 版本:1.12.9 简单的HTTP服务器代码: package main import ( "net/http" ) type TestHandler struct ...

  8. 异步IO与回调

    最好了解 Java NIO 中 Buffer.Channel 和 Selector 的基本操作,主要是一些接口操作,比较简单. 本文将介绍非阻塞 IO 和异步 IO,也就是大家耳熟能详的 NIO 和 ...

  9. [转帖]腾讯云TStack获下一代云计算技术创新奖 与鲲鹏等产品实现兼容性测试

    http://www.techweb.com.cn/cloud/2019-12-16/2769286.shtml [TechWeb]12 月 16 日消息,在中国电子技术标准化研究院主办的“第九届中国 ...

  10. MongoDB学习笔记（五）

    MongoDB 查看执行计划 MongoDB 中的 explain() 函数可以帮助我们查看查询相关的信息,这有助于我们快速查找到搜索瓶颈进而解决它,本文我们就来看看 explain() 的一些用法及 ...