How to add icons to inputs?

If you want to prepend or append an icon to a text input, you can use the following code (when using bootstrap):

Code:

<div class="input-group">
   <span class="input-group-addon">@</span>
   <input type="text" class="form-control" placeholder="Username">
</div>

or, although not tested, using the form_input method:

Code:

<div class="input-group">
   <span class="input-group-addon">@</span>
   <?php echo form_input($fielddata); ?>
</div>