Chiusura Form e Salvataggio Automatico

Imports System.Data.SqlClient

Public Class Form1
Inherits System.Windows.Forms.Form


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DG e' una datagridwiev
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Private da As SqlDataAdapter
Private ds As DataSet

Private Sub Form1_Load(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles MyBase.Load
' Create a Connection object

Dim dbConn As New SqlConnection("server=(local); database=pubs; integrated security=true")

' Create the data adapter object pointing to the authors table

da = New SqlDataAdapter( _
"SELECT au_id, au_lname, au_fname, phone FROM authors", dbConn)

' Fill the DataSet

ds = New DataSet("Authors")
da.Fill(ds)

' Display the records in a DataGrid component

dg.DataSource = ds.Tables(0)
End Sub


Private Sub Form1_Closing(ByVal sender As Object, _
ByVal e As System.ComponentModel.CancelEventArgs) Handles MyBase.Closing

' Message box to prompt the save request

If (MessageBox.Show("Do you want save the changes?", _
"Update", _
MessageBoxButtons.YesNo) = DialogResult.Yes) Then
Try

' Create the insert, delete and update statements automatically

Dim cb As New SqlCommandBuilder(da)

' Retrieve just the changed rows

Dim dsChanges As DataSet = ds.GetChanges()

If Not dsChanges Is Nothing Then

' Update the database

da.Update(dsChanges)

' Accept the changes within the DataSet

ds.AcceptChanges()
End If
Catch ex As Exception

' Error occurs, show the message

MessageBox.Show(ex.Message)
End Try
End If
End Sub