DOT NET Interview Questions - DotNetSpider

Note :- Small sample of OLEDB is provided in “WindowsAppOleDb” which uses
“Nwind.mdb” in bin directory to display data in Listbox.
Private Sub loadData()
Dim strPath As String
strPath = AppDomain.CurrentDomain.BaseDirectory
Dim objOLEDBCon As New
OleDbConnection(“Provider=Microsoft.Jet.OLEDB.4.0;Data Source =” &
strPath & “Nwind.mdb”)
Dim objOLEDBCommand As OleDbCommand
Dim objOLEDBReader As OleDbDataReader
Try
End Sub
objOLEDBCommand = New OleDbCommand(“Select FirstName
from Employees”)
objOLEDBCon.Open()
objOLEDBCommand.Connection = objOLEDBCon
objOLEDBReader = objOLEDBCommand.ExecuteReader()
Do While objOLEDBReader.Read()
lstNorthwinds.Items.Add(objOLEDBReader.GetString(0))
Loop
Catch ex As Exception
Throw ex
Finally
objOLEDBCon.Close()
End Try
The main heart is the “Loaddata()” method which actually loads the data in listbox.
Note:- This source code has the connectionstring hard coded in the program itself which is
not a good programming practice.For windows application the best place to store
connectionstring is “App.config”.Also note “AppDomain.CurrentDomain.BaseDirectory”
function this gives the current path of the running exe which is “BIN” and the MDB file is
in that directory.Also note the finally block which executes irrespective that there is error or
not.Thus ensuring that all the connection to the datastore is freed.It’s best practice to put all
clean up statements in finally block thus ensuring that the resources are deallocated properly.
(B) How do we connect to SQL SERVER , which namespace
do we use ?
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* Where do you see yourself after three years ?