var userInfo = wx.getStorageSync('userInfo');

var phoneNo = "userInfo.phoneNo";

var mobile = this.data.mobile;

this.setData({

[phoneNo]: mobile

});

wx.setStorageSync("userInfo", userInfo );

我想实现给这个userInfo里面的phoneNo赋值，这样写是报错的。请问该怎么样做才能成功？