Changing href's to footnotes

Question

Here is exactly what I am trying to do. I have a file with many commands of the form \href{a}{b} for strings a and b. I would like to redefine \href so that it executes the following: \footnote{\href{a}{b}}. Thus want to change the URL's into footnotes to URL's. – Is this possible?

Answer 1

This can be done using the standard \let technique:

\let\oldhref=\href
\renewcommand{\href}[2]{\footnote{\oldhref{#1}{#2}}}

Answer 2

This solution also works with URLs that include active characters such as &, % and # (requires hyperref):

\makeatletter
\newcommand\hreffootnote@[2]{\footnote{\hyper@linkurl{\Hurl{#2}}{#1}}}
\DeclareRobustCommand{\hreffootnote}{\hyper@normalise\hreffootnote@}
\makeatother

However, as far as I understand your blog post, you actually want that \href{a}{b} behaves like b\footnote{\url{a}}. This can be achieved as follows:

\makeatletter
\newcommand\myhref@[2]{#2\footnote{\url@{#1}}}
\DeclareRobustCommand{\myhref}{\hyper@normalise\myhref@}
\makeatother

Also, see my answer to this question.

Answer 3

The first argument of \href must be handled as verbatim which makes redefinitions tricky. Michael Ummels's answer correctly shows how to use hyperrefs internal macros for this. However, the recent update of my newverbs package provides a way to collect an argument verbatim easily:

\documentclass{article}

\usepackage{hyperref}
\usepackage{newverbs}[2011/07/24]

\let\orighref\href
\renewcommand{\href}{\Collectverb{\hrefii}}
\newcommand\hrefii[2]{\footnote{\orighref{#1}{#2}}}

\usepackage{lipsum}% Dummy text
\begin{document}

\lipsum*[1]\href{http://test.com/%$^£$%^_@~}{Test URL}

% With other argument separators as { }:
\lipsum*[2]\href|http://test.com/%$^£$}{%^_@~|{Test URL}

% If a real \href is wanted (also used for comparison here)
\lipsum*[3]\orighref{http://test.com/%$^£$%^_@~}{Test URL}

\end{document}