helpcenter/Web/App_Code/BaseContentUserControls.cs

using System;
using System.Web.UI;

public class BaseContentUserControls : UserControl
{
    public string PageCaption { get; set; }
    public string PageTitle { get; set; }
    public string MetaDescription { get; set; }
    public string MetaKeyWords { get; set; }

    protected new virtual void Init() { }

    protected override void OnInit(EventArgs e)
    {
        base.OnInit(e);

        PageCaption = PageTitle = string.Empty;

        Init();
    }

    public void UpdatePage()
    {
        if(Page is BasePage)
        {
            BasePage bp = Page as BasePage;

            if(!string.IsNullOrEmpty(PageCaption) && string.IsNullOrEmpty(bp.PageCaption))
            {
                bp.PageCaption = PageCaption;
            }
            if (!string.IsNullOrEmpty(PageTitle) && string.IsNullOrEmpty(bp.PageTitle))
            {
                bp.PageTitle = PageTitle;
            }
            if (!string.IsNullOrEmpty(MetaDescription)&& string.IsNullOrEmpty(bp.MetaDescription))
            {
                bp.MetaDescription = MetaDescription;
            }
            if (!string.IsNullOrEmpty(MetaKeyWords) && string.IsNullOrEmpty(bp.MetaKeyWords))
            {
                bp.MetaKeyWords = MetaKeyWords;
            }
        }
    }
}