VB.Net » Database ADO.net » Filter

Use Filter to filter Data Table

Imports System
Imports System.Data
Imports System.Data.SqlClient

public class MainClass
Shared Sub Main()
Dim thisConnection As New SqlConnection("server=(local)\SQLEXPRESS;" & _
"integrated security=sspi;database=MyDatabase")

' Sql Query
Dim sql As String = "SELECT ID, FirstName, LastName FROM Employee"

Try
' Create Data Adapter
Dim da As New SqlDataAdapter
da.SelectCommand = New SqlCommand(sql, thisConnection)

' Create and fill Dataset
Dim ds As New DataSet
da.Fill(ds, "Employee")

' Get the Data Tables Collection
Dim dtc As DataTableCollection = ds.Tables

' Get and Display First Data Table
' 1. Display header
Console.WriteLine("Results From Employee Table")
Console.WriteLine("FirstName".PadRight(25) & " | LastName")

' 2. Set display filter
Dim filter1 As String = "FirstName = 'Joe'"

' 3. Set sort
Dim sort1 As String = "LastName asc"

' 4. Display filtered and sorted data
For Each row As DataRow In dtc("Employee").Select(filter1, sort1)
Console.WriteLine("{0} | {1}", _
row("FirstName").ToString().PadRight(25), _
row("LastName"))
Next

Catch ex As SqlException
' Display error
Console.WriteLine("Error: " & ex.ToString())
Finally
' Close Connection
thisConnection.Close()
Console.WriteLine("Connection Closed")
End Try
End Sub
End Class

VB.Net » Database ADO.net

Simple Connection String

Imports System
Imports System.Data
Imports System.Data.OleDb
Imports System.Data.SqlClient
Imports System.Collections
Imports System.Windows.Forms
Imports System.Resources

Public Class MainClass
Shared Sub Main()
'Declare variables and objects
Dim strConnectionString As String = _
"Provider=Microsoft.Jet.OLEDB.4.0;" & _
"Data Source=Employee.mdb;"
Dim objConnection As New OleDbConnection(strConnectionString)
Dim strSQL As String = _
"SELECT FirstName, LastName FROM Employee"
Dim objCommand As New OleDbCommand(strSQL, objConnection)
Dim objDataAdapter As New OleDbDataAdapter(objCommand)
Dim objDataTable As New Data.DataTable("Employee")
Dim objDataRow As DataRow

Try
'Open the database connection
objConnection.Open()

'Fill the DataTable object
objDataAdapter.Fill(objDataTable)

'Load the list box on the form
For Each objDataRow In objDataTable.Rows
Console.WriteLine(objDataRow.Item("FirstName") & " " & _
objDataRow.Item("LastName"))
Next
Catch OleDbExceptionErr As OleDbException
'Write the exception
Console.WriteLine(OleDbExceptionErr.Message)
Catch InvalidOperationExceptionErr As InvalidOperationException
'Write the exception
Console.WriteLine(InvalidOperationExceptionErr.Message)
End Try

'Close the database connection
objConnection.Close()

'Clean up
objDataRow = Nothing
objDataTable.Dispose()
objDataTable = Nothing
objDataAdapter.Dispose()
objDataAdapter = Nothing
objCommand.Dispose()
objCommand = Nothing
objConnection.Dispose()
objConnection = Nothing

End Sub
End Class