Replace pairs of symbols in chat text with html tags to style as bold, italic, and strikethrough

I am trying to make a whatsapp style text post. When user create text like this:

*Hi* ~how are you~ _where are you?_

then this text is automatically changing like this

Hi how are you where are you

I know i can do it with php regex like this:

The example is for bold text:

function makeBoldText($orimessage){
    $message = $orimessage;
    $regex = "/*([w]*)*/";
    $message = preg_replace($regex, '<strong>$0</strong>', $message);
    return  $message ;
}
echo makeBoldText($message);

But there is a problem it should be remove * when text is outputed.

The other regex also should be like this:

Bold:

/*([w]*)*/ 

Italic:

/_([w]*)_/ 

strikethrough:

 /~([w]*)~/

My question is, can I do all this in one regex? And can the special characters be deleted when the output is made?

Answer

You may use a single call to preg_replace_callback here:

$styles = array ( '*' => 'strong', '_' => 'i', '~' => 'strike');

function makeBoldText($orimessage) {
   global $styles;
   return preg_replace_callback('/(?<!w)([*~_])(.+?)1(?!w)/',
      function($m) use($styles) { 
         return '<'. $styles[$m[1]]. '>'. $m[2]. '</'. $styles[$m[1]]. '>';
      },
      $orimessage);
}

// call it as:
$s = '*Hi* ~how are you~ _where are you?_';
echo makeBoldText($s);
//=> <strong>Hi</strong> <strike>how are you</strike> <i>where are you?</i>