Closing Webpage Without Prompt

Add Javascript to webpage


    function AssignContent()
    {
        window.open('', '_self', '');
        window.close();
    }

Add C# code at webpage aspx page.


        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                if (!ClientScript.IsClientScriptBlockRegistered("k1"))
                {
                    ClientScript.RegisterClientScriptBlock(this.GetType(), "k1", "<script language='javascript'>AssignContent();</script>");
                }
            }
        }

During form onload the webpage will close.