getPhoneNumber返回undefined

getPhoneNumber: function (e) {//点击获取手机号码按钮

var that = this;

wx.checkSession({

success: function () {

console.log(e.detail.errMsg)

console.log(e.detail.iv)

console.log(e.detail.encryptedData)

---

console.log(e.detail.iv)

console.log(e.detail.encryptedData)

以上这二个返回都是undefined

不知道是什么原因，麻烦指点