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

There is already an open DataReader associated with this Connection which must be closed first的更多相关文章
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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..........
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Fixing the "There is already an open DataReader associated with this Command which must be clos ...
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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 ...
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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 ...
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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 ...
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This can be easily solved by allowing MARS in your connection string. Add MultipleActiveResultSets=t ...
- 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 ...
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