<p>This is probably explained more easily with an example. I'm trying to find a way of turning a relative URL, e.g. "/Foo.aspx" or "~/Foo.aspx" into a full URL, e.g. <a href="http://localhost/Foo.aspx" rel="noreferrer">http://localhost/Foo.aspx</a>. That way when I deploy to test or stage, where the domain under which the site runs is different, I will get <a href="http://test/Foo.aspx" rel="noreferrer">http://test/Foo.aspx</a> and <a href="http://stage/Foo.aspx" rel="noreferrer">http://stage/Foo.aspx</a>.</p>

<p>Any ideas?</p>

Have a play with this (modified
from here
)
```
```
public string ConvertRelativeUrlToAbsoluteUrl(string relativeUrl) {
    return string.Format("http{0}://{1}{2}",
        (Request.IsSecureConnection) ? "s" : "", 
        Request.Url.Host,
        Page.ResolveUrl(relativeUrl)
    );
}
```
```