Fancyhdr: How can I change the header on the table of contents pages?

Question

I have employed fancyhdr to modify the headers of the chapters and sections to fit my taste. They are now written in lower case and alternate on even and odd pages:

\documentclass[a4paper]{book}
\usepackage[finnish]{babel}

\usepackage{fancyhdr}
\pagestyle{fancy}
\renewcommand{\sectionmark}[1]{\markright{\thesection\ #1}}
\renewcommand{\chaptermark}[1]{\markboth{#1}{}}
\fancyhead{} % clear all header fields
\fancyfoot{} % clear all footer fields.
\fancyhead[LE]{\textsl{\leftmark}}   % L = left;  E = even pages
\fancyhead[RO]{\textsl{\rightmark}}  % R = right; O = odd pages
\fancyhead[RE]{\thepage}             % R = right; E = even pages
\fancyhead[LO]{\thepage}             % L = left;  O = odd pages

\begin{document}
\tableofcontents
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\chapter{Xxx}
\section{Yyy}
\section{Yyy}
\section{Yyy}
\end{document}

The headers on the table of contents pages are still in uppercase. How can I extend my mofifications to apply the table of contents pages in full as well? I have included the call to babel in case it matters.

Answer 1

Use no \nouppercase which is provided by fancyhdr for the header and footer fields:

\documentclass[a4paper]{book}
\usepackage[finnish]{babel}

\usepackage{fancyhdr}
\pagestyle{fancy}
\renewcommand{\sectionmark}[1]{\markright{\thesection\ #1}}
\renewcommand{\chaptermark}[1]{\markboth{#1}{}}
\fancyhf{} % clear all header and footer fields
\fancyhead[LE]{\textsl{\nouppercase{\leftmark}}}%<- changed
\fancyhead[RO]{\textsl{\nouppercase{\rightmark}}}%<- changed
\fancyhead[RE]{\thepage}
\fancyhead[LO]{\thepage}

\usepackage{lipsum}% only for dummy text
\begin{document}
\tableofcontents
\chapter{Xxx}
\section{Yyy}
\lipsum[1-50]
\end{document}

Answer 2

You can add this to your preamble:

\makeatletter
\renewcommand\tableofcontents{%
 \if@twocolumn
 \@restonecoltrue\onecolumn
 \else
 \@restonecolfalse
 \fi
 \chapter*{\contentsname
 \@mkboth{%
 \contentsname}{\contentsname}}%
 \@starttoc{toc}%
 \if@restonecol\twocolumn\fi
 }
\makeatother