Question

So on my Default.aspx page I have several listboxes which I am populating on page_load.

However, if the user changes these listboxes and wants to restore the original settings, I want a button at the top, which is defined in the Site.Master, to call this same function gain to restore the original values.

How can I obtain a reference to an instance of the _Default object from the Site.Master file? Is there a way to globally access the instance of _Default that is called when the page is first loaded? Or do I need to store that manually somewhere?

For example:

Default.aspx.cs:

namespace WebApplication1
{
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            setConfigurationData();
        }

        public void setConfigurationData()
        {
            //Do stuff to elements on Default.aspx

Site.Master.cs

namespace WebApplication1
{
    public partial class SiteMaster : System.Web.UI.MasterPage
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void RefreshMenu1_MenuItemClick(object sender, MenuEventArgs e)
        {
            //Need to call this function from an instance of _Default, but I don't know
            //how to retrive this or save it from when it is first created

            //_Default.setConfigurationData();

Answer 1

Add this class scoped variable to your Master page

private System.Web.UI.Page currentContentPage = new System.Web.UI.Page();

Then add this method to your Master page

public void childIdentity(System.Web.UI.Page childPage)
{
    currentContentPage = childPage;
}

Now in the Page_Load of your Default page add

SiteMaster masterPage = Page.Master as SiteMaster;
masterPage.childIdentity(this);

Now your master page should be able to access the objects on the Default page through the reference in its currentContentPage variable.