formatting of the table of contents

Question

How can I change the settings of my table of contents, so that the sections and subsections are not indented as shown in the second picture. I would also like to center the title of the Contents. I am using the article class.

Answer 1

This is an approach which uses the »tocstyle« package with the tocflat option along with the standard style.

\documentclass[11pt]{article}
\usepackage[T1]{fontenc}

\usepackage[tocflat]{tocstyle}
\usetocstyle{standard}

\usepackage{blindtext}

% Redefinition of ToC command to get centered heading
\makeatletter
\renewcommand\tableofcontents{%
  \null\hfill\textbf{\Large\contentsname}\hfill\null\par
  \@mkboth{\MakeUppercase\contentsname}{\MakeUppercase\contentsname}%
  \@starttoc{toc}%
}
\makeatother

\begin{document}
  \tableofcontents

  \blinddocument
\end{document}

You can compare with the tocfullflat option for equidistant spaces between numbers and heading entries. More details can be found in the package manual.

N.B.: You will get a warning about the alpha status of the package. So far is has not caused any major problems for me.

---

Answer 2

Using the tocloft package, all you have to do is to set the indents to the same values: 0em (so entries are flushed to the left margin) and 2em (space to typeset the unit number). Using \cfttoctitlefont and \cftaftertoctitle you can center the title; I also set tocdepth to 2 since subsubsections are not to be listed according to the image:

\documentclass{article}
\usepackage{tocloft}

\cftsetindents{section}{0em}{2em}
\cftsetindents{subsection}{0em}{2em}

\renewcommand\cfttoctitlefont{\hfill\Large\bfseries}
\renewcommand\cftaftertoctitle{\hfill\mbox{}}

\setcounter{tocdepth}{2}

\begin{document}

\tableofcontents
\clearpage

\section*{Introduction}
\addcontentsline{toc}{section}{Introduction}
\section{Test section one}
\subsection{Test subsection}
\subsection{Test subsection}
\subsubsection{Test subsubsection}
\subsection{Test subsection}

\section{Test section two}
\subsection{Test subsection}
\subsection{Test subsection}
\subsubsection{Test subsubsection}
\subsection{Test subsection}

\end{document}

Answer 3

Here's a solution using titletoc package; it defines the dottedcontents command which has syntax:

% \dottedcontents{<section>}[<left>]{<above-code>}
% {<label width>}{<leader width>}

I have also used the command

\renewcommand{\contentsname}{\centering Contents}

to center the table of contents title.

Here's the code:

% arara: pdflatex
% arara: pdflatex
\documentclass{article}
\usepackage{titletoc}

% \dottedcontents{<section>}[<left>]{<above-code>}
% {<label width>}{<leader width>}
\dottedcontents{section}[0em]{\bfseries}{2.9em}{1pc}
\dottedcontents{subsection}[0em]{}{3.3em}{1pc}

% center the toc heading
\renewcommand{\contentsname}{\centering Contents}

\begin{document}

\tableofcontents

\section*{Introduction}
\addcontentsline{toc}{section}{Introduction}
\section{Test section one}
\subsection{Test subsection}
\subsection{Test subsection}
\subsection{Test subsection}

\section{Test section two}
\subsection{Test subsection}
\subsection{Test subsection}
\subsection{Test subsection}

\end{document}

For further reading, see How to modify the space between the numbers and text of sectioning titles in the table of contents?.