jQuery addClass example

Change class name on click in jQuery

HTML

<textarea>
  
</textarea>
<div>
  <span data-size = '40'></span>
</div>

CSS

div { width: 100px; border:1px solid;}
span {color:#f00; font-size:40px; border:2px solid #0f0;   }

JavaScript

$('textarea').on('keyup', function(){
	$('span').text($(this).val());
  
	size = parseInt($('span').data('size'));
  
  if($('span').width() > $('div').width()) { 	
  	$('span').css({'font-size' : (size - 5) + 'px'}).data('size', (size - 5))
    
  }
})

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jQuery addClass example

Change class name on click in jQuery

HTML

CSS

JavaScript

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Join the 4+ million users, and keep the JSFiddle dream alive.

Ad-free

Use pre-released features

Fiddle collections

Private collections and fiddles

Console