jQuery validate 验证radio实例

<div class="row cl"> 
  <label class="form-label col-xs-4 col-sm-3"><span class="c-red">*</span>优惠券类型：</label> 
  <div class="formControls col-xs-8 col-sm-9 skin-minimal"> 
    <div class="radio-box"> 
      <input name="couponType" type="radio" value="1" id="couponType_1" <#if couponInfo.couponType == 1>checked</#if 
      <label for="couponType_1">满减券</label> 
    </div> 
    <div class="radio-box"> 
      <input type="radio" name="couponType" value="2" id="couponType_2" <#if couponInfo.couponType == 2>checked</#if 
      <label for="couponType_2">折扣券</label> 
    </div> 
    <div class="radio-box"> 
      <input type="radio" name="couponType" value="3" id="couponType_3" <#if couponInfo.couponType == 3>checked</#if 
      <label for="couponType_3">现金券</label> 
    </div> 
  <label id="couponType-error" for="couponType" class="error"></label> 
  </div> 
</div> 
<div class="row cl" id="couponMax_div"> 
  <label class="form-label col-xs-4 col-sm-3">优惠最高金额：</label> 
  <div class="formControls col-xs-8 col-sm-9"> 
    <input type="text" class="input-text" placeholder="仅在折扣券的情况下填写" name="couponMax" id="couponMax" value="${couponInfo.couponMax}"> 
  </div> 
</div> 

$("#form-member-add").validate({ 
  rules:{ 
    sendCouponType:{ 
      required:true 
    }, 
    platformId:{ 
      required:true 
    }, 
    couponType:{ 
      required:true 
    } 
  }, 
  onkeyup:false, 
  focusCleanup:true, 
  success:"valid", 
  submitHandler:function(form){ 
    var couponInfo = getCouponParameter(); 
    saveCouponInfo(couponInfo); 
  } 
}); 
function saveCouponInfo(couponInfo){ 
  $.ajax({ 
    type:'POST', 
    url: "/coupon/save", 
    data: { 
      couponStr:couponInfo 
    }, 
    async: false, 
    success: function(data){ 
      if(data.code == 200){ 
        var index = parent.layer.getFrameIndex(window.name); 
        parent.$('#btn_search').click(); 
        parent.layer.close(index); 
      }else layer.alert("操作失败"); 
    } 
  });  
} 
// 获取优惠券表单值 
var getCouponParameter = function(){ 
  var couponInfo = {}; 
  couponInfo.id = couponId; 
  //优惠券活动名称 
  couponInfo.couponName = $('#couponName').val(); 
  //使用范围 
  couponInfo.couponUsingRange = $("input[name='couponUsingRange']:checked").val(); 
  //发放类型 
  couponInfo.sendCouponType = $("input[name='sendCouponType']:checked").val(); 
  //使用平台 
  couponInfo.platformId = $("input[name='platformId']:checked").val(); 
  //优惠券类型 
  couponInfo.couponType = $("input[name='couponType']:checked").val(); 
  //优惠券使用限制 
  couponInfo.meetPrice = $('#meetPrice').val(); 
  //优惠券面额 
  couponInfo.couponAmount = $('#couponAmount').val(); 
  //活动起始时间 
  couponInfo.couponStartDate = $('#couponStartDate').val(); 
  //活动结束时间 
  couponInfo.couponEndDate = $('#couponEndDate').val(); 
  //优惠券数量 
  couponInfo.couponNum = $('#couponNum').val(); 
  //用户领取优惠券数量限制 
  couponInfo.limitGetNum = $('#limitGetNum').val(); 
  //备注 
  couponInfo.remark = $('#remark').val(); 
  return JSON.stringify(couponInfo); 
} 
$("input:radio[name='couponType']").click(function(){ 
  //1.满减券   2.折扣券    3.现金券 
  var tt = $(this).val(); 
  switch(tt){ 
    case '1' : 
      $('#couponMax_div').hide(); 
      break; 
    case '2' : 
      $('#couponMax_div').show(); 
      break; 
    case '3' : 
      $('#couponMax_div').hide(); 
      break; 
    default: 
      break; 
  } 
});