从Master更新内容页面

Question

I have a master page and a content page. Not quite sure how to do this. How do I reset/refresh the content page after I do something in the Master page. The something I'm doing is changing a dropdown list and which then dictates what you can see in the content page. If I could call the page load of the content page from the master page that would do it.

Thank you

Answer 1

Handle a custom event of the masterpage in the page.

//Event in MasterPage
public delegate void SomethingSelected(object sender, String SelectedValue);
public event SomethingSelected OnSomethingSelected;

//SelectedIndexChanged event in MasterPage
protected void DropDonwnList1_SelectedIndexChanged(object sender, EventArgs e)
{
    OnSomethingSelected(sender, ((DropDownList)sender).SelectedValue);
}

The content page(assuming the type of it is called SiteMaster ):

protected void Page_Init(object sender,EventArgs e){
    var master = (SiteMaster)Page.Master;
    master.OnSomethingSelected +=  MasterSelected;
}

private void MasterSelected(object sender, string selectedValue)
{ 
    // now you can handle the master's event and update your content page
}

Answer 2

For the sequence of events, see http://msdn.microsoft.com/en-us/library/ms178472.aspx . Specically, " Master pages behave like child controls on a page: the master page Init event occurs before the page Init and Load events, and the master page Load event occurs after the page Init and Load events. "