vb.net中的数据读取器问题 [英] datareader problem in vb.net

问题描述

大家好
我有一个小查询，例如从itemmaster中选择前1个，其中itemcode ="XXXXX''
上面的查询从itemaster表返回1行

但是当我使用sqldatareader从vb.net调用此查询时，它返回了0行，我找不到解决方案，请给我一些扩展的想法

这是我的代码

hi all
i have small query like ''select top 1 from itemmaster where itemcode=''XXXXX''
this above query returning 1 row from itemaster table

but when i call this same query from vb.net using sqldatareader its return 0 row, i couldn''t find the solution pls give me some idea exparts

this is my code

dim qry as string = 'select top 1 from itemmaster where itemcode=XXXXX' 
dim openrs1 as sqldatareader
Dim cmd As New SqlCommand(qry, myConnectionstring)
       cmd.Connection = con1
       OpenRs1 = cmd.ExecuteReader()

推荐答案

即使使用代码片段更新了问题，它看起来也不完整，对您说的话没有多大意义.

在这里查看如何使用DataReader从数据库中获取数据:

Even after updating question with code snippet, it looks incomplete and does not makes much sense on what you say.

Look here on how to use DataReader to fetch data from database:

Using connection
        Dim command As SqlCommand = New SqlCommand( _
          "SELECT CategoryID, CategoryName FROM Categories;", _
          connection)
        connection.Open()

        Dim reader As SqlDataReader = command.ExecuteReader()

        If reader.HasRows Then
            Do While reader.Read()
                Console.WriteLine(reader.GetInt32(0) _
                  & vbTab & reader.GetString(1))
            Loop
        Else
            Console.WriteLine("No rows found.")
        End If

        reader.Close()
    End Using

参考:
使用DataReader(ADO.NET)检索数据 [ ^ ]
DataReader类 [

Refer:
Retrieving Data Using a DataReader (ADO.NET)[^]
DataReader Class[^]

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