用JavaScript解决Placeholder的IE8兼容问题

        <script type="text/javascript">
        if( !('placeholder' in document.createElement('input')) ){

            $('input[placeholder],textarea[placeholder]').each(function(){
                var that = $(this),
                        text= that.attr('placeholder');
                if(that.val()===""){
                    that.val(text).addClass('placeholder');
                }
                that.focus(function(){
                    if(that.val()===text){
                        that.val("").removeClass('placeholder');
                    }
                })
                        .blur(function(){
                            if(that.val()===""){
                                that.val(text).addClass('placeholder');
                            }
                        })
                        .closest('form').submit(function(){
                            if(that.val() === text){
                                that.val('');
                            }
                        });
            });
        }
    </script>


http://www.cnblogs.com/jifeng/p/3983368.html