como obtener datos de un datagrid a un textbox

[DeweyVidal]

Hola soy nuevo encuanto a programacion en .Net y necesito de su gran ayuda....
Estoy haciendo un sistema y en ciertas partes necesito buscar registros almacenados en una BS`s, los arroja en un datagrid, hasta ahi todo va bien, pero necesito que cuando seleccione una fila del datagrid me los pase a un textbox...

Les dejo mi codigo para ke puedan analizarlo:

Imports System.Data
Imports System.Data.SqlClient
Public Class RefaccionDiscoDuro
Inherits System.Web.UI.Page
Private conjuntoDatos As DataSet
Public MyConnection As New SqlConnection
Protected WithEvents textboxmarca As System.Web.UI.WebControls.TextBox
Protected WithEvents datosgridBusqueda As System.Web.UI.WebControls.DataGrid
Protected WithEvents Textboxtipo As System.Web.UI.WebControls.TextBox
Protected WithEvents TextboxModelo As System.Web.UI.WebControls.TextBox
Protected WithEvents TextboxTamaño As System.Web.UI.WebControls.TextBox
Protected WithEvents Label2 As System.Web.UI.WebControls.TextBox
Private adaptador As SqlDataAdapter
#Region " Código generado por el Diseñador de Web Forms "

'El Diseñador de Web Forms requiere esta llamada.
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

End Sub
Protected WithEvents Image1 As System.Web.UI.WebControls.Image
Protected WithEvents Button3 As System.Web.UI.WebControls.Button
Protected WithEvents Button6 As System.Web.UI.WebControls.Button
Protected WithEvents Button5 As System.Web.UI.WebControls.Button
Protected WithEvents LinkButton9 As System.Web.UI.WebControls.LinkButton
Protected WithEvents LinkButton4 As System.Web.UI.WebControls.LinkButton
Protected WithEvents LinkButton1 As System.Web.UI.WebControls.LinkButton
Protected WithEvents LinkButton6 As System.Web.UI.WebControls.LinkButton
Protected WithEvents Button1 As System.Web.UI.WebControls.Button
Protected WithEvents Button8 As System.Web.UI.WebControls.Button
Protected WithEvents Button7 As System.Web.UI.WebControls.Button
Protected WithEvents Button4 As System.Web.UI.WebControls.Button

'NOTA: el Diseñador de Web Forms necesita la siguiente declaración del marcador de posición.
'No se debe eliminar o mover.
Private designerPlaceholderDeclaration As System.Object

Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: el Diseñador de Web Forms requiere esta llamada de método
'No la modifique con el editor de código.
InitializeComponent()
End Sub

#End Region

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
MyConnection.ConnectionString = _
"Data Source=(local);" & _
"Initial Catalog=Sistema;" & _
"User=sa; Password=;"
End Sub


Private Sub LinkButton9_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LinkButton9.Click
Response.Redirect("RefaccionMouse.aspx")
End Sub

Private Sub LinkButton4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LinkButton4.Click
Response.Redirect("RefaccionTeclado.aspx")
End Sub

Private Sub LinkButton6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LinkButton6.Click
Response.Redirect("RefaccionTarjetaRed.aspx")
End Sub

Private Sub LinkButton7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Response.Redirect("RefaccionDiscoDuro.aspx")
End Sub

Private Sub LinkButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LinkButton1.Click
Response.Redirect("RefaccionMemoriaRAM.aspx")
End Sub



Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click
Response.Redirect("menuRefacciones.aspx")
End Sub

Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
Response.Redirect("Consultas.aspx")
End Sub



Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Response.Redirect("Solicitudes.aspx")
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
adaptador = New SqlDataAdapter("SELECT Marca, Tipo, Tamaño,Modelo FROM Tab_Disco_Duro", MyConnection)
Dim comando As SqlCommandBuilder = New SqlCommandBuilder(adaptador)
conjuntoDatos = New DataSet
MyConnection.Open()
adaptador.Fill(conjuntoDatos, "Tab_Disco_Duro")
MyConnection.Close()
DataBind()
Me.adaptador.Update(conjuntoDatos, "Tab_Disco_Duro")

Dim vista As New DataView
vista.Table = conjuntoDatos.Tables("Tab_Disco_Duro")
vista.RowFilter = "Marca = '" & Me.textboxmarca.Text & "'"
Me.datosgridBusqueda.DataSource = vista
DataBind()
End Sub
End Class


Espero pronto su respuesta...