How to ADO.NET OleDbDataReader
OleDbDataReader Object provides a connection oriented data access to the OLEDB Data Sources. ExecuteReader() in the OleDbCommand Object send the SQL statements to OleDbConnection Object and populate an OleDbDataReader Object based on the SQL statement.
Dim oledbReader As OleDbDataReader = oledbCmd.ExecuteReader()
When the ExecuteReader method in OleDbCommand Object execute , it instantiate an OleDb.OleDbDataReader Object. When started to read from an OleDbDataReader it should always be open and positioned prior to the first record. The Read() method in the OleDbDataReader is used to read the rows from OleDbDataReader and it always moves forward to a new valid row, if any row exist .
OleDbDataReader.Read()
Imports System.Data.OleDb
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim connetionString As String
Dim oledbCnn As OleDbConnection
Dim oledbCmd As OleDbCommand
Dim sql As String
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here like Select * from product"
oledbCnn = New OleDbConnection(connetionString)
Try
oledbCnn.Open()
oledbCmd = New OleDbCommand(sql, oledbCnn)
Dim oledbReader As OleDbDataReader = oledbCmd.ExecuteReader()
While oledbReader.Read
MsgBox(oledbReader.Item(0) & " - " & oledbReader.Item(1) & " - " & oledbReader.Item(2))
End While
oledbReader.Close()
oledbCmd.Dispose()
oledbCnn.Close()
Catch ex As Exception
MsgBox("Can not open connection ! ")
End Try
End Sub
End Class |
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here like Select * from product"
You have to replace the string with your realtime variables.
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