自定义应用程序页面中的SharePoint SPContext.List

I have a custom SharePoint application page deployed to the _layouts folder. It's a custom "new form" for a custom content type. During my interactions with this page, I will need to add an item to my list. When the page first loads, I can use SPContext.Current.List to see the current list I'm working with. But after I fill in my form and the form posts back onto itself and IsPostBack is true, then SPContext.Current.List is null so I can't find the list that I need to add my stuff into.I have a custom SharePoint application page dep