edit grid view data for windows form

Textbox1.text = datagridview1.currentrow.cells(i).value
'where i is the poistion in the row that you want get out

Imports System.Data.SqlClient
Dim myConnection As SqlConnection = New SqlConnection()
Dim sql as string
myConnection.ConnectionString = 'your ConnectionString here
myConnection.Open()
sql = "insert into <tablename> (col1, col2,col3,col4)values('" & _
textbox1.text & "','" & textbox2.text & "','" & textbox3.text & "','" & _
textbox4.text & "')"
myConnection.execute sql
myConnection.Close()</tablename>

Private Sub btnDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDelete.Click
       Dim rowToDelete As Int32 = Me.DataGridView1.Rows.GetFirstRow( _
       DataGridViewElementStates.Selected)
       If rowToDelete > -1 Then
           Me.DataGridView1.Rows.RemoveAt(rowToDelete)
       End If
     '----------- This will delete ur grid row
     '-- I am not familiar with sql server and i think u know well to delete  
     'row from database
     ' U can use like this to update database

       Dim sql As String

       sql = "delete from table name where strClassName = '" &  txtClass.text & "'"

       connection.execute(sql)  ' connection is sqlconnection object



   End Sub

    Private Sub DataGridView1_CellContentDoubleClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellContentDoubleClick, DataGridView1.CellClick, DataGridView1.CellContentClick

...

'DS=Dataset=Datasource for the DatagridView
'In THins case DS contains only one table
'and the colum is known (In this example it is the colum with the ID 0)
'You can also use the COlum name instead 
'dim content as string = ds.Tables(0).Rows(Row).Item("ID")


Dim Row As Integer = e.RowIndex()
dim content as string = ds.Tables(0).Rows(Row).Item(0)



End Sub

Private Sub cmdSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdSave.Click
        Dim sqlConnection As SqlClient.SqlConnection = New SqlClient.SqlConnection("YOUR SQL CONNECTION STRING")
        Dim sqlcmd As SqlCommand = New SqlCommand("YOUR SQL SEARCH = THE SAME AS FOR THE DATAGRID")

  sqlConnection.Open()

        Dim da As New SqlDataAdapter(sqlcmd)
        Dim dsDb As New DataSet
        da.Fill(dsDb)


        Dim cb As New SqlClient.SqlCommandBuilder(da)

        da.InsertCommand = cb.GetInsertCommand
        da.DeleteCommand = cb.GetDeleteCommand
        da.UpdateCommand = cb.GetUpdateCommand

'DA=Your New DataAdapter and dsDB = orginal Dataset form DB
'ds = your Old DataSet which is connected to the DatagridView

        Try

            da.Update(ds.Tables(0))
        Catch ex As Exception
            MessageBox.Show(Convert.ToString(ex))
        End Try

        sqlConnection.Close()

'REfresh Datagrid is an Method form my Programm.. I can recommend to refresh the datagrid now with the content form your database - so you can check if the command was succesfull
        refreshDatagrid()
    End Sub