Public Class clsSearchinDatagrid
    Public Function Search(ByVal str As String, ByVal dg As DataGrid) As Integer
         Try
            dg.Select()
            Dim intRows As Integer = CType(dg.DataSource, DataView).Count - 1
            For i As Integer = 0 To intRows
                Dim strdg As String = dg(i, 0).ToString.ToLower()
                dg.UnSelect(i)
                If strdg.StartsWith(str) Then
                    dg.Select(i)
                    Return i
                End If
            Next
            Return -1
          Catch ex As ArgumentException
            MessageBox.Show(ex.Message.ToString)
        End Try
 
    End Function
End Class

Public Class clsSearchinDatagridView
    Public Function Search(ByVal str As String, ByVal dgv As DataGridView) As _
      Integer
        Try
            For Each dgvr As DataGridViewRow In dgv.Rows
                dgvr.Selected() = True
            Next
            Dim intRows As Integer = CType(dgv.DataSource, BindingSource).Count _
              - 1
            For i As Integer = 0 To intRows
                Dim strdgv As String = dgv(i, 0).ToString.ToLower()
               dgv.SelectedRows(i).Selected() = False
                If strdgv.StartsWith(str) Then
                    dgv.SelectedRows(i).Selected() = True
                    Return i
                End If
            Next
            Return -1
           Catch ex As ArgumentException
            MessageBox.Show(ex.Message.ToString)
        End Try
    End Function

VB@rchiv its the Best