typescript 在 Angular 2/4 中刷新前执行函数
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/48061430/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Execute function before refresh in Angular 2/4
提问by MeVimalkumar
On HTMLpage, When user click / press F5button page refresh but before refresh I want to execute one function or a simple alert.
在HTML页面上，当用户单击/按下F5按钮页面刷新但在刷新之前我想执行一个功能或一个简单的警报。
User can click on refresh button, press F5or Ctrl + R.
用户可以点击刷新按钮，按F5或Ctrl + R.
using Angular2/4
使用Angular2/4
采纳答案by codeSetter
You need to rely on browser events here.
您需要在此处依赖浏览器事件。
window.onbeforeunload = (ev) => {
this.myFunction();
// OR
this.yuorService.doActon().subscribe(() => {
alert('did something before refresh');
});
// OR
alert('goin to refresh');
// finally return the message to browser api.
var dialogText = 'Changes that you made may not be saved.';
ev.returnValue = dialogText;
return dialogText;
};
回答by ConnorsFan
The refresh of the page should trigger the event handler bound to window:beforeunload. This stackblitzshows how to implement it for the "Home" component, using HostListener. You can test the page refresh by executing it in full page mode.
页面刷新应触发绑定到 的事件处理程序window:beforeunload。这个 stackblitz展示了如何为“Home”组件实现它，使用HostListener. 您可以通过在整页模式下执行来测试页面刷新。
import { Component, HostListener } from '@angular/core';
@Component({
...
})
export class HomeViewComponent {
@HostListener("window:beforeunload", ["$event"]) unloadHandler(event: Event) {
console.log("Processing beforeunload...");
// Do more processing...
event.returnValue = false;
}
...
}
