\documentclass[a4paper,12pt,twoside]{report}
\usepackage{titlesec}
\titleformat{\chapter}[display]{}{\chaptername}{-2pt}{\hskip5cm \centering \Huge \bfseries \mbox}
\titlespacing{\chapter}{0pt}{-112pt}{27pt}
\begin{document}
\chapter{test}
blablabla
\end{document}
我怎样才能\titlespacing{\chapter}{0pt}{-112pt}{27pt}在偶数页和\titlespacing{\chapter}{0pt}{-112pt}{27pt}奇数页上有？