pbootcms表单提交样例代码 js过滤是否输入

<form action="{pboot:msgaction}"  method="post" id=myform>  <ul class="liu_ul">
        <li class="clearfix">
        <p class="p1"> <span><i>*</i>姓名</span><input type="text" name="name" id="name"></p>
        <p> <span><i>*</i>电话</span><input type="text" name="tel" id="tel"></p>
      </li>
       
      <li> <span class="span_nei">留言内容</span>
        <textarea name="content" id="attr_5" rows="7" cols=""></textarea>
      </li>
     
      <li class="btn"> <a href="javascript:void(0);" onclick="checkForm();">提交</a> &nbsp; <a href="javascript:void(0);" onclick="resetFrom();">重置</a> </li>
      </ul>
    </form>
    
     </div>
  <!--footer  start-->
  <script type="text/javascript">
            function checkForm()
            {
              if(document.getElementById('name').value.length == 0)
              {
                alert('请输入您的姓名');
                return false;
              }
              if(document.getElementById('tel').value.length == 0)
              {
                alert('请输入您的电话');
                return false;
              }
              document.getElementById('myform').submit();
            }
			
			//清除表单中所有内容
			function resetFrom() {
				window.location.reload();
			}
          </script>