根页Ionic2 -ionViewWillenter()事件

Question

我想通过从本地检索值来自动登录，但是我无法做到它没有给出任何错误，也没有任何错误，我无法执行查询。请引导我穿过右门。

````

ionViewWillEnter()   {
      alert("Check Will Enter in Login Page");
      console.log("Login Screen");
    {
      this.database.executeSql("SELECT * FROM user DESC LIMIT 1", []).then((userdata) => {
        {
          let toast = this.toastCtrl.create({
            message: 'User is validated successfully',
            duration: 3000,
            position: 'bottom'
          });
          toast.onDidDismiss(() => {
            console.log('Dismissed toast');
          });
          toast.present();
        }
        this.navCtrl.push(DashboardPage);
         alert("1" + JSON.stringify(userdata));
         alert("Check login_id-" + userdata.rows.item(0).login_id);
         alert("Check password-" + userdata.rows.item(0).password);
        alert("Check password-" + userdata.rows.item(0).mobile_no);
         alert("DeviceID CHECK retrieving from USER" + userdata);
      }, (error) => {
        alert("AUTO LOGIN ERROR" + JSON.stringify(error));
      });
    }
  }

````

Answer 1

您必须在platform.ready()方法内调用您的SQL执行。

 ionViewWillEnter() :void  {
    this.platform.ready().then(() => {
          ///your sql and other code
    })