typescript Angular Router Events: NavigationEnd -- 如何只过滤最后一个事件
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原文地址: http://stackoverflow.com/questions/49722369/
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Angular Router Events: NavigationEnd -- How to filter only the last event
提问by Lynx 242
I want to extract only the last event entry of type NavigationEndfrom router.events. But somehow I can't find a proper way to do this. Whatever I try the following code snipped is the only way to get access to these objects of interest.
我只想从 router.events 中提取NavigationEnd 类型的最后一个事件条目。但不知何故，我找不到合适的方法来做到这一点。无论我尝试什么，以下代码都是访问这些感兴趣的对象的唯一方法。
let ne: any;
router.events.filter(e => e instanceof NavigationEnd)
.forEach(e => {
ne = e as NavigationEnd;
});
console.log('target page: ', ne.urlAfterRedirects);
But do I really have to use .forEach() letting it run though all entries and using then the last entry? Isn't there a better way to handle the events as a kind of array and then say
但是我真的必须使用 .forEach() 让它运行所有条目并使用最后一个条目吗？有没有更好的方法来处理事件作为一种数组然后说
ne = arrayOfEvents[arrayOfEvents.length-1]
?
?
I'm getting crazy about it but it seems that I can't see the wood for the trees...
我对此很着迷，但似乎只见树木不见森林......
回答by Simon_Weaver
PS. There's a better way to filter using an instanceof typeguard, you then get the proper type without having to assert it again:
附注。有一种更好的方法可以使用instanceof typeguard进行过滤，然后您无需再次断言即可获得正确的类型：
firstChildData$ = this.router.events.pipe(
filter((e): e is NavigationEnd => e instanceof NavigationEnd),
map(e => { // e is now NavigationEnd }
回答by Lynx 242
Okay, after reading through the posted articles above and rethinking what I really want to achieve I found out that my approach was definitely too complicated. Because actually I only need access to the currently called route. And so I started from scratch and came across this small but very effective solution:
好吧，在阅读了上面发布的文章并重新思考我真正想要实现的目标后，我发现我的方法绝对太复杂了。因为实际上我只需要访问当前调用的路由。所以我从头开始，遇到了这个小但非常有效的解决方案：
this.router.events.subscribe(value => {
console.log('current route: ', router.url.toString());
});
Thanks to all who shared a comment in oder to support me! It helped al lot as I was able to tie up loose ends.
感谢所有分享评论以支持我的人！它帮了我很大的忙，因为我能够把松散的东西绑起来。
