How to obtain the space left to bottom of page

Question

Since it is impossible to use \vfill inside a framebox, is there any way of getting the current height position of text? I want to fill in a framebox so that it uses all the space left on a page, instead of trial and error...

Answer 1

Is there any way of getting the current height position of text?

If this were your only question, then you have the answer in Aditya's \measurepage in How to define a figure size so that it consumes the rest of a page?

I don't consider your question as duplicate though since it is specific to using \framebox which cannot take a macro directly as height using \framebox(<width>,<height>){<>} syntax. A possibility using Aditya's \measurepage macro is to use \parbox as in the MWE below.

\documentclass[]{article}
\usepackage[showframe]{geometry}
\usepackage{lipsum}

\newcommand\measurepage{\dimexpr\pagegoal-\pagetotal-\baselineskip\relax}
\newcommand{\MyFrameBox}[1]{%
{\addtolength{\linewidth}{%-\marginparsep
-9.5pt}
\noindent
\framebox{
\parbox[t][\measurepage]{\linewidth}{
#1
}}}}
\begin{document}
\lipsum[1-2]

\MyFrameBox{\lipsum[1]}
%
%Here is the next text
\end{document}

The showframe option of the geometry was just used here so that you can see where the text ends.