# How to change the style of chapter?

I am trying to make my own style of chapter. It was nearly successful...However,two problems arised.First, the style also appears in content that's not what I want.Second, the position of the blue bar is wrong. How can I solve the two problems? Thanks! Here is an example code:

\documentclass{book}
\usepackage{titlesec}
\usepackage{tikz}
\usepackage{xcolor}

\titleformat{\chapter}[display]{%
\begin{tikzpicture}
\path [fill=blue!20] (0,1) rectangle (\textwidth,2);
\end{tikzpicture}
\flushleft%
}{\fontsize{96pt}{96pt}\bfseries\thechapter}{0pt}{\Huge\color{blue}}

\begin{document}
\tableofcontents
\chapter{example1}
\section{hahaha}
\chapter{example2}
\section{sososos}
\end{document}


Like this?

\documentclass{book}
\usepackage{titlesec}
\usepackage{tikz}
\usepackage{xcolor}

\titleformat{\chapter}[display]{%
\flushleft%
}{
\begin{tikzpicture}
\node[anchor=south west] (chap) at (0.1,1.3){\fontsize{96pt}{96pt}\bfseries\thechapter};
\path [fill=blue!20] (0,1) rectangle (\textwidth,0);
\path(0,-0.2);
\end{tikzpicture}
}{-3mm}{\Huge\color{blue}}

\begin{document}
\tableofcontents
\chapter{example1}
\section{hahaha}
\chapter{example2}
\section{sososos}
\end{document}