Format the text in JavaScript alert box

javascript html format alert

66,402

Solution 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.

Solution 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:

Solution 3

You can not style the text inside an alert box. But you can use a modal box solution instead, here's a list to get you started:

Solution 4

In my case I created internationalization through a JavaScript file. I needed a mnemonic on each button so I was looking for an easy solution. Actually, I've an easy approach to get the wanted result:

\u0332 is the Unicode Character COMBINING LOW LINE

With this character you can underline single letters.

Demonstration:

alert('S\u0332earch - s underlined');

i18n = {};

i18n.SEARCH = "S\u0332earch - s underlined";

document.getElementById('search').innerHTML = i18n.SEARCH;