Is there an easy way to "hide" an environment with an if statement?

Question

What I want is something like this:

\hidemyenvironment
\begin{myenvironment}
     This text is not displayed, it is "hidden".
\end{myenvironment}
\showmyenvironment
\begin{myenvironment}
     This text is visible!
\end{myenvironment}

I want the command \hidemyenvironment to make it not appear on the PDF, while the command \showmyenvironment will make it reappear again. I was thinking of using an if statement so I can switch it on and off in the document and have some environments displayed and others hidden.

Here is a MWE:

\documentclass{article}
\usepackage[utf8]{inputenc}
\makeatletter
\newif\if@hidemyenvironment
\newcommand{\hidemyenvironment}{\@hidemyenvironmenttrue}
\newcommand{\showmyenvironment}{\@hidemyenvironmentfalse}

\newenvironment{myenvironment}{
     \if@hidemyenvironment
      % some code to ignore the environment?
     \else
     % just show whatever is in the environment/ do nothing
     \fi
}{}
\makeatother

\begin{document}
Hello!\par

\hidemyenvironment
\begin{myenvironment}
     Hidden text!
\end{myenvironment}
\par

\showmyenvironment
\begin{myenvironment}
     \begin{equation}
           x+y=z
     \end{equation}
\end{myenvironment}

\end{document}

Is there perhaps a command that can comment everything inside the environment, or another solution? I would prefer that you can write equations, tables and other things inside the environment and that it is only used to hide/ display parts of the output PDF.

The output of the MWE should be:

Answer 1

You can do this using the comment package.

\documentclass{article}
\usepackage{comment}

\begin{document}

Hello!

\excludecomment{myenvironment}
\begin{myenvironment}
     Hidden text!
\end{myenvironment}

\includecomment{myenvironment}
\begin{myenvironment}
     \begin{equation}
           x+y=z
     \end{equation}
\end{myenvironment}

\end{document}

Feel free to add

\newcommand{\hidemyenvironment}{\excludecomment{myenvironment}}
\newcommand{\showmyenvironment}{\includecomment{myenvironment}}

Also, your use of \par is unnecessary.