Hi

Today is your lucky day :)

- Create the files below and put both in the /usercontrols directory
- Change "altTemplateAlias" in the second file from "myAltTemplate" to whatever you want
- Goto Developer -> DataTypes and create a new Datatype
- Select umbraco usercontrol wrapper as the Render Control
- Select AltTemplateLink.ascx from the usercontrol dropdown
- Save
- Add the new datatype to a doctype

Oh yeah, and get a Windows machine with Visual Studio :)

AltTemplateLink.ascx

<%@ Control Language="C#" AutoEventWireup="true" CodeFile="AltTemplateLink.ascx.cs" Inherits="AltTemplateLink" %>
<asp:HyperLink ID="lnkAltTemplate" runat="server"></asp:HyperLink>

AltTemplateLink.ascx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using umbraco;
using umbraco.editorControls;

public partial class AltTemplateLink : System.Web.UI.UserControl, umbraco.editorControls.userControlGrapper.IUsercontrolDataEditor  
{
    string altTemplateAlias = "myAltTemplate";
    string linkText = "Click Me";
    
    
    protected void Page_Load(object sender, EventArgs e)
    {
        int nodeId = int.Parse(HttpContext.Current.Request.QueryString["id"].ToString());

        lnkAltTemplate.Text = linkText;
        lnkAltTemplate.NavigateUrl = umbraco.library.NiceUrl(nodeId) + "?altTemplate=" + altTemplateAlias;
        lnkAltTemplate.Target = "_blank";
    }
    
    private string _umbracoValue;

    public object value {
        get
        {
            return "";
        }
        set
        {
            _umbracoValue = value.ToString();
        }
    }
}