Format the text in JavaScript alert box

Question

How can I format the text in a JavaScript alert box? I need a word in the text to be underlined.

Answer 1

You can use only:

\b = Backspace  \f = Form feed  \n = New line  \r = Carriage return  \t = tab \000 = octal character  \x00 = hexadecimal character  \u0000 = hexadecimal unicode character 

So, you can insert different ASCII characters, but not format them (like italic or bold).

EDIT I also have to mention, that in fact alert acts like toString conversion, so including tags and/or styles is not possible.

Answer 2

Underline a string using unicode character '\u0332', called a COMBINING LOW LINE

function underline(s) {     var arr = s.split('');     s = arr.join('\u0332');     if (s) s = s + '\u0332';     return s; }  var str = underline('hello world'); // "h̲e̲l̲l̲o̲ ̲w̲o̲r̲l̲d̲"  alert(str); 

This method is not guaranteed to produce a smooth underline.

Example of confirm() on Firefox 59: