ADO.NET ExecuteReader in OleDbCommand Object
ExecuteReader() in OleDbCommand Object send the SQL statements to Connection Object and populate a OleDbDataReader Object based on the SQL statement. When the ExecuteReader method in OleDbCommand Object execute , it instantiate a OleDb.OleDbDataReader Object.
The OleDbDataReader Object is a stream-based , forward-only, read-only retrieval of query results from the Data Source, which do not update the data. The OleDbDataReader cannot be created directly from code, they created only by calling the ExecuteReader method of a Command Object.
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 cnn As OleDbConnection
Dim cmd As OleDbCommand
Dim sql As String
Dim reader As OleDbDataReader
connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
sql = "Your SQL Statement Here like Select * from product"
cnn = New OleDbConnection(connetionString)
Try
cnn.Open()
cmd = New OleDbCommand(sql, cnn)
reader = cmd.ExecuteReader()
While reader.Read()
MsgBox(reader.Item(0) & " - " & reader.Item(1) & " - " & reader.Item(2))
End While
reader.Close()
cmd.Dispose()
cnn.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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