Modal Popup with Gridview [Resolved]

In my First Page i have a text box and button.

When i click button a new pop with grid view data should open.

After selecting the row in grid view the selected row value should be display in text box and modal should be closed.

I can open the grid view with data but can't able to close and get the value to my text box.

Please help needed.

Thanks

Code for opening popup:

<asp:Button ID="Button1" runat="server" Text="Fill Form in Popup" OnClick="Button1_Click" />

<cc1:ModalPopupExtender ID="mp1" runat="server" PopupControlID="Panl1" TargetControlID="Button1"
CancelControlID="Button2" BackgroundCssClass="Background">
</cc1:ModalPopupExtender>
<asp:Panel ID="Panl1" runat="server" CssClass="Popup" style = "display:none">
<iframe style=" width: 350px; height: 300px;" id="irm1" src="GridViewTest.aspx" runat="server"></iframe>
<br/>
<asp:Button ID="Button2" runat="server" Text="Close" />
</asp:Panel>

<asp:TextBox ID="TextBox1" runat="server" ></asp:TextBox>

[Resolved]