Verbatim text can't be shown correctly in pdf

Question

I try to change the font of verbatim text as below

% Used by @verbatim ... @endverbatim
\newenvironment{DoxyVerb}{%
  \verbatim%
  \fontencoding{OT1}\fontfamily{ptm}\fontseries{m}\fontshape{n}%
  \fontsize{10pt}{10}\selectfont%
}{%
  \endverbatim%
  \normalsize%
}

But I don't know why some characters cannot be shown in pdf

The example call is the verbatim text in the above figure. The variable name should be parameter_table_build_number, but pdf shows the underscore as an upper dot. I copied that dot and paste into notepad, it shows me the underscore. I searched the underscore in pdf, and it also indicates that dot is the underscore.

However, if I change the font to \footnotesize, it show me the correct character but the verbatim text will exceeds the paper's boundary.

Could anybody tell me how to fix this problem? Thanks a lot.

Answer 1

You can't use \verbatim ... \endverbatim inside a macro. A detailed explanation you can find here: TeX Frequently Asked Questions - Why doesn’t verbatim work within …?

You can use packages like listings, fancyvrb ...

Here an example with fancyvrb:

\documentclass[]{scrartcl}
\usepackage[T1]{fontenc}
\usepackage{fancyvrb}

\DefineVerbatimEnvironment{DoxyVerb}{Verbatim}%
   {fontfamily=ptm,fontseries=m,fontshape=n}

\begin{document}
\begin{DoxyVerb}
get_asd_asd
\end{DoxyVerb}
\end{document}

EDIT: Using listings:

\documentclass[]{scrartcl}
\usepackage[T1]{fontenc}
\usepackage{listings}
\lstnewenvironment{lstDoxyVerb}%
    {\lstset{basicstyle=\fontsize{10pt}{10}\usefont{OT1}{ptm}{m}{n}}}%
    {}
\begin{document}


\begin{lstDoxyVerb}
get_asd_asd
\end{lstDoxyVerb}
\end{document}