reference to a label linked with a longtable row

Question

Is there a way to link to a specific row in a Longtabl environment. This is usefull when using the hyperref package and allows the viewer to simply jump from somewhere in the document to the right row of the table. At the moment one jumps always to the top of the column?

For instance:

\begin{longtable}
\label{r1}cell1a&cell1b&cell1c&cell1d&cell1e\\
\label{r2}cell2a&cell2b&cell2c&cell2d&cell2e\\
\label{r3}cell3a&cell3b&cell3c&cell3d&cell3e\\
\label{r4}cell4a&cell4b&cell4c&cell4d&cell4e\\
\end{longtable}

As one can see in \hyperref[r3]{row 3}...

Answer 1

Have a look at the macros \hypertarget and \hyperlink of the hyperref package.

One can create an internal link (almost) anywhere in the document -- including some row in a tabular environment -- with the instruction

\hypertarget{<name>}{<text>}

where <name> should be a unique "label" that will be used by hyperref to create the "target" and <text> should be whatever should be placed there. E.g., in a tabular environment, <text> could be the content of the first cell of a certain row. You can then link to that "label" elsewhere in the document with the command

\hyperlink{<name>}{<text>}

where <name> should be the label you chose in the \hypertarget command and <text> can be anything that passes TeX's syntax rules; e.g., it could be the string "there".

Answer 2

If you always wish to refer to explicit rows in the text (by text) it seams obvious that you will not change your table often. Therefore you can automate the referencing using Mico's suggestions.

I have created a new table environment which automatically creates labels for the tables according to a user defined prefix, furthermore there is a correction to the anchor placement to enable the correct linking:

\begin{refltable}{<table format>}{<ref prefix>}

This can be used in the following way:

\documentclass{article}
\usepackage{hyperref,array,longtable}

\newcounter{tablerowno}
% New environment for the longtable, this will set it up correctly
\makeatletter
\newenvironment{refltable}[2]{%
    \setcounter{tablerowno}{0}
    \begin{longtable}{>{\stepcounter{tablerowno}\raisebox{\f@size pt}{\phantomsection}\label{#2\thetablerowno}}#1}}%
  {%
    \end{longtable}%
}
\makeatother
% In order for the link to pop-up the correct row we have to raise
% the anchor of the link, this is done using the size of the font (\f@size).
% This will also capture \Huge, \LARGE, etc.

\begin{document}

\begin{refltable}{cl}{r}
  Content of row 1 \\
  Content of row 2 \\  Content of row 3 \\
  Content of row 4 \\  Content of row 5 \\
  Content of row 6 \\  Content of row 7 \\
  Content of row 8 \\  Content of row 9 \\
  Content of row 10\\
  Content of row 11\\
  Content of row 12
\end{refltable}
As one can see in \hyperref[r10]{row 10} and \hyperref[r1]{row 1}.


\begin{refltable}{cl}{secr}
  Content of row 1 \\
  Content of row 2 \\  Content of row 3 \\
  Content of row 4 \\  Content of row 5 \\  
  Content of row 6 \\  Content of row 7 \\  
  Content of row 8 \\  Content of row 9 \\  
  Content of row 10\\
  Content of row 11\\
  Content of row 12
\end{refltable}
As one can see in \hyperref[secr10]{row 10} and \hyperref[secr1]{row 1} together with \hyperref[r1]{row 1} of the first table.

\end{document}

However, you might be better off by using the manual way by Mico as it would ensure that you dont accidentally reference a wrong row in the table.