js清空form表单里的值，清空input ，清空select

	清空form表单选择项：

	<div class="screen-window">
		<form action="/Index/index" method="post" class="form-horizontal group-border hover-stripped">
			<select class="control" name="clients_belong" >
				<option value="">请选择</option>
				<option value="1">你好</option>
			</select>
			
			<input type="text" name="timea" value=''>
			<input type="text" name="timeb" value=''>
			
			<button type="submit">确认提交</button>
			<button id="qingkong" type="button">清空筛选</button>
		</form>	
	</div>
	
	<script src="/Public/js/jquery-1.8.3.min.js" type="text/javascript" charset="utf-8"></script>
	<script type="text/javascript">
		$("#qingkong").click(function(){
			$(".screen-window form input").each(function(){
				$(this).val('');
			});
			$(".screen-window form select").each(function(){
				$(this).val('');
			});
		})
	</script>