wx.login({
 success: function(res) {
 console.log('loginCode', res.code)
 }
});

https://api.weixin.qq.com/sns/jscode2session?appid=APPID&secret=SECRET&js_code=JSCODE&grant_type=authorization_code

<button open-type="getPhoneNumber" bindgetphonenumber="getPhoneNumber"></button>
 
Page({
 getPhoneNumber: function(e) {
 console.log(e.detail.errMsg)
 console.log(e.detail.iv)
 console.log(e.detail.encryptedData)
 }
})