Prevent a paragraph break before a section heading

Question

How can I prevent a paragraph break before a section heading? To prevent it after, I know that I can use runin like

\titleformat{\section}[runin]{\Large\bf}{\thesection\quad}{0pt}{}

However, how can I prevent before? I want something like:

1. First section heading Text... (no line break here) 2. Second Section Heading Text...

---

EDIT. I am trying in the following way for \subsection. I created a new command like:

\newcommand{\subsectionnlb}[1]{
   \stepcounter{subsection}
   {\normalfont\bf\thesubsection \hspace{0.3em} #1\hspace{0.3em}}
}

How can I call the formatting of \subsection and apply to the custom command \subsectionnlb?

Answer 1

If you don't need to use \section specifically, you can try the following workaround:

\documentclass{scrartcl}
\usepackage{blindtext}
\newcounter{sect}%          Creates a counter to be used in the new section command
\newcommand\Section[1]{%    Defines a new section command:
 \addtocounter{sect}{1}%    Increases counter
 \addcontentsline{toc}{section}{\arabic{sect}.~#1}% Add to table of contents
  {\sectfont% This command is intended to use with scrartcl class; 
%    if not using it you can use any formatting command you wish
  \arabic{sect}.~#1.}}%    Prints "<section number>. <section title>"
\begin{document}
\tableofcontents
\blindtext
\Section{A first section}
\blindtext
\Section{A second section}
\blindtext
\end{document}

EDIT: BTW, this workaround doesn't use (it's actually incompatible with) titlesec package, but I assumed (based on your last comment) that you didn't actually required it.