ModalPopupExtender problem.

Question

I have taken ModalPopupExtender and in the panel iframe , i have set the src or iframe at run time.
when ModalPopupExtender open then i want to click on the save button of src page which have in the model popup currently and at this event i want to close this modal popup and want to refresh. How can i do this?

<cc1:ModalPopupExtender ID="ModalPopupExtender1" runat="server"
     okcontrolid="btnOkay"
    targetcontrolid="btnAdd"
    popupdraghandlecontrolid="PopupHeader" drag="true"
    >
    </cc1:ModalPopupExtender>
    
    
    <asp:Button ID="btnAdd" runat="server" onclick="Button1_Click" Text="ADD" />
 
&nbsp;<asp:Button ID="btnUpdate" runat="server" onclick="btnUpdate_Click"
        Text="UPDATE" />
&nbsp;
    <asp:Button ID="btnDelete" runat="server" onclick="btnDelete_Click"
        Text="DELETE" />
    <br />
    
    
    
    <asp:panel id="Panel_StudentProspects" style="display: none" runat="server" >
            <div class="popup_Container" style="size:auto">
            
                <div class="popup_Titlebar" id="Div1">
                    <div class="TitlebarLeft">Student Prospects</div>
                    <div id="spcancelcross"class="TitlebarRight"  ></div>
                </div>

                <iframe id="frameeditexpanse" frameborder="0" runat="server"
                    scrolling="auto" style="width:550px; height:500px;"></iframe>
                  
                   
                   
            </div>
             <input id="btnOkay" type="button" value="Done" />
                    <input id="btnCancel" type="button" value="Cancel" />
    </asp:panel>