Jquery 解决 H5 placeholder元素问题

<style type="text/css">
.placeholder{
	color: #cacaca;
}
</style>

<script type="text/javascript">
	$(function(){
		if(!placeholderSupport()){   // 判断浏览器是否支持 placeholder
		    $(‘[placeholder]‘).focus(function() {
		        var input = $(this);
		        if (input.val() == input.attr(‘placeholder‘)) {
		            input.val(‘‘);
		            input.removeClass(‘placeholder‘);
		        }
		    }).blur(function() {
		        var input = $(this);
		        if (input.val() == ‘‘ || input.val() == input.attr(‘placeholder‘)) {
		            input.addClass(‘placeholder‘);
		            input.val(input.attr(‘placeholder‘));
		        }
		    }).blur();
		};
	})
	function placeholderSupport() {
	    return ‘placeholder‘ in document.createElement(‘input‘);
	}
</script>

<input id="keywords" placeholder="请输入名称、地址、组织机构代码等关键字查询"/>