我的显示按钮代码如下.但是它给出了错误消息msg，因为它是朋友，因此无法访问dr [英] hiiiiii my code for display button is below. but it give error msg that dr is not accessible as it is a friend

问题描述

Dim cmd As New SqlCommand
        cmd.CommandText = "select * from tbsumeet1"
        cmd.Connection = con
        Dim dr As New SqlDataReader
        dr = cmd.ExecuteReader
        ListBox1.DataTextField = "ename"
        ListBox1.DataValueField = "en"
        ListBox1.DataSource = dr
        ListBox1.DataBind()

推荐答案

在定义数据读取器时删除关键字New.这是因为ExecuteReader在内部执行New并返回创建的DataReader.因此，无需直接创建DataReader的实例.

因此，请更改此内容:

Remove the keyword New while defining datareader. This is because ExecuteReader does New internally and returns DataReader created. So, no need to directly create the instance of DataReader.

So, change this:

Dim dr As New SqlDataReader

至:

to:

Dim dr As SqlDataReader

请参考:讨论过类似的问题 [ ^ ]

Refer: Similar issue discussed[^]

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