微信小程序中函数事件的执行顺序

问题描述：做页面跳转的时候，发现从登录页跳转到首页之后马上又跳转回登录页。

分析问题：微信小程序中请求与后续事件不是按照顺序执行的，而是有可能先执行后面的，之后再返回执行success函数。因此把页面跳转写进success函数里之后。问题解决。

//正确则进入五大明星产品页

              if (res.data.state === '1'){

                //获取code并发送给后台

                wx.login({

                  success:function(res){

                    if (res.code) {

                      wx.request({

                        url: 'https://wectest.com/Wechat/LoginSessionID',

                        data:{

                          code:res.code,

                          verifyID:that.data.verifyID

                        },

                        header:{

                          'content-type': 'application/json'

                        },

                        success:function(res){

                          console.log('sessionID')

                          console.log(res)

                          var sessionID = res.data.sessionID;

                          wx.setStorageSync('sessionID', sessionID)

                          if (sessionID) {

                            wx.navigateTo({

                              url: '../products/products',

                            })

                          }

                        }

                      })

                    }

                  }

                })