将ViewState移出页面？

protected override void Render(HtmlTextWriter writer)
{
    Page.ViewStateMode = ViewStateMode.Disabled;
    base.Render(writer);
}

protected override object LoadPageStateFromPersistenceMedium()
{
    return Session["ViewState"];
}

protected override void SavePageStateToPersistenceMedium(object viewState)
{
    Session["ViewState"] = viewState;
}

public class CustomViewStateProvider : ViewStateModeProvider
{
    public override bool LoadPageState(Page page, out object viewState)
    {
        // Load ViewState from custom location
        viewState = LoadViewStateFromCustomLocation(page);
        return true;
    }

    public override void SavePageState(Page page, object viewState)
    {
        // Save ViewState to custom location
        SaveViewStateToCustomLocation(page, viewState);
    }
}