如何计算加载控制器在 2 个事件 - present() 和 dismiss() -IONIC 2 之间的时间

Question

我已经在我的组件上实现了加载控制器，它从json api带来数据，我希望达到计算的时间将数据带到页面上。

请找到我实现的代码OnInit listproduct.ts

export class ListproductPage implements OnInit{
  public list = [];
  loading;chkfromservice;
  constructor(private _listProduct : ListproductService,private _deleteProduct : DeleteProductService,
              public navCtrl: NavController,public navParams: NavParams,public loadingCtrl: LoadingController) {
                this.loading = this.loadingCtrl.create({
                  content: 'Please wait...'
                });
              }
      ngOnInit() {
        this.loading.present();
         this._listProduct.listProduct().subscribe(data => {
           this.list = data;
           console.log(this._listProduct.checkfromservice);
           this.chkfromservice = this._listProduct.checkfromservice;
          console.log(data[0].NAME);
          this.loading.dismiss();
          });
      }

请注意，我需要计算 this.loading.present(); 和 this.loading.dismiss(); 之间的时间.微秒

Answer 1

您可以在启动加载程序之前存储日期，也可以在关闭加载程序后再次存储日期。然后，您可以获得两个日期之间的差异。下面是一个示例代码。

  ngOnInit() {
    let start = new Date(); // Get the date just before presenting your loader
    this.loading.present();
     this._listProduct.listProduct().subscribe(data => {
       this.list = data;
       console.log(this._listProduct.checkfromservice);
       this.chkfromservice = this._listProduct.checkfromservice;
      console.log(data[0].NAME);
      this.loading.dismiss();
      let end = new Date(); // Get the date just after dismissing your loader
      let diff = (end.getTime() - start.getTime()); // Get the time difference in milliseconds
      console.log(diff);
      });
  }

有关如何

计算时差的更多详细信息，请参阅此答案。