Labelify 介绍
A jQuery plugin to add labels to your textboxes.
A fairly common design pattern in web forms is to have some explanatory help
text for a textfield appear inside the text field, and then remove it when the
user clicks into that field. It has the benefit of putting the help precisely
where the user’s looking.
This plugin takes text from a <label> element or a title attribute or from
anywhere else you choose and adds that text as help, a “tooltip”, inside the
textbox.