在Angular Typescript中将函数作为参数传递的方式之间的差异

Question

What is the difference between these two lines of code (except the fact that second line has an inline function calling "setThing"). I noticed that on the first case Angular change detection didn't run.

someObservable<Thing>.subscribe<Thing>(this.setThing) // change detection didn't run
someObservable<Thing>.subscribe<Thing>(thing => this.setThing(thing)); // change detection worked

setThing(thing :Thing) {
    this.thing = thing;
}

Answer 1

Assuming you are using this inside the function. In the first one you lose the lexical this , in the second you don't.

Example:

First one:

setThing(thing :Thing) {
    this.myTemplateThing = thing; // Since your this is not refering to the component you won't be seeing a change
}