<form bindsubmit="formBindsubmit" bindreset="formReset">
 <view style="display:flex;">
  <label>用户名：</label>
  <input name="userName" placeholder="请输入用户名！" />
 </view>
 <view style="display:flex;">
  <label>密码：</label>
  <input name="psw" placeholder="请输入密码！" password="true" />
 </view>
 <view style="display:flex;margin-top:30px;">
  <button style="width:30%;" formType="submit" >登录</button>
  <button style="width:30%" formType="reset" >重置</button>
 </view>
</form>
<view>{{tip}}</view>
<view>{{userName}}</view>
<view>{{psw}}</view>

Page({
 data:{
  // text:"这是一个页面"
  tip:'',
  userName:'',
  psw:''
 },
 formBindsubmit:function(e){
  if(e.detail.value.userName.length==0||e.detail.value.psw.length==0){
   this.setData({
    tip:'提示：用户名和密码不能为空！',
    userName:'',
    psw:''
   })
  }else{
   this.setData({
    tip:'',
    userName:'用户名：'+e.detail.value.userName,
    psw:'密码：'+e.detail.value.psw
   })
  }
 },
 formReset:function(){
  this.setData({
   tip:'',
   userName:'',
   psw:''
  })
 }
})