Keeping grid data in a usercontrol by retrieving the criteria from the parent - user-controls

Question

I have a usercontrol that I want to have the grid inside so I don't have to duplicate that grid on every page. Except when I sort, page, or anything that does a post back the usercontrol reloads and loses its datasource. My plan is to retrieve the search criteria from the parent page(since it already has it from the criteria controls). That way when the NeedDataSource is called it still has the criteria to pass back the right results.
How do I get where you see SuperSearch to be whichever page might be the parent like StateToState.
public SearchCriteria SearchCriteria
{
get
{
Page parent = this.Page;
if (parent != null)
{
var superSearch = parent as SuperSearch;
if (superSearch != null) return superSearch.SearchCriteria;
}
return new SearchCriteria();
}
}

Answer 1

Create an event handler 'event EventHandler NeedSearchCriteria' on your usercontrol that gets fired on your parent page
On your aspx page:
<UC:Grid runat="server" ID="ucGrid" OnNeedSearchCriteria="ucGrid_OnNeedSearchCriteria" />
In the code behind:
public void ucGrid_OnNeedSearchCriteria(object sender, EventArgs e)
{
ucGrid.Criteria = Criteria;
}
And on the usercontrol code behind:
public event EventHandler NeedSearchCriteria;
private SearchCriteria _criteria;
public SearchCriteria Criteria
{
get
{
if (_criteria == null && NeedSearchCriteria != null)
{
NeedSearchCriteria(this, new EventArgs());
}
return _criteria ?? new SearchCriteria();
}
set
{
_criteria = value;
}
}