Question

这是我的代码：

@echo off
setlocal EnableDelayedExpansion
for /f "usebackq tokens=1,9,10,11,12 delims= " %%a in ("all.txt") do (
    if "%%b"=="count:" if "%%d"=="inuse:" (
        set "feature=%%a"
        set "count=%%c"
        set "inuse=%%e"
        echo count: !count!
        echo inuse: !inuse!
        echo feature: !feature!
        echo.
    )
)
pause

因为@Component({ selector: "foo", template: ` <span>Init : {{o.init}}</span> <span>Loaded data : {{o.loadedData}}</span> `, providers: [ Services ] }) export class FooComponent implements OnInit{ constructor (private _services: Services) {} o: Object ngOnInit() { o = {"init": "foo"} this.services.randomCall() .subscribe( res => this.o["loadedData"] = res["loadedData"] ) } }和模板渲染之间的竞争条件，o.loadedData每次都不会出现。我希望在分配randomCall()后通知角度。在angular1中，我会调用范围的o["loadedData"] = res["loadedData"]函数。

我怎样才能在angular2中做类似的事情？

谢谢！

编辑：我加回了这个，这是一个错字。

Answer 1

我会使用this关键字：

o: Object
ngOnInit() {
  this.o = {"init": "foo"}; // <-----

  this.services.randomCall()
      .subscribe(
          res => {
            this.o["loadedData"] = res["loadedData"]; // <-----
          }
      );
 }

修改

您可以强制Angular2使用ChangeDetectorRef类检测更改，这样：

constructor(private cdr:ChangeDetectorRef) { } o: Object ngOnInit() { this.o = {"init": "foo"}; this.services.randomCall() .subscribe( res => { this.o["loadedData"] = res["loadedData"]; this.cdr.detectChanges(); // <----- } ); }

Answer 2

通常这是通过Angulars更改检测来完成的，该检测由其区域通知应该发生更改检测。当以某种方式在Angulars区域外运行的代码修改您的模型时，您可以手动调用更改检测，如

export class FooComponent implements OnInit{
   constructor (private _services: Services, private cdRef:ChangeDetectorRef) {}

   o: Object
   ngOnInit() {
      o = {"init": "foo"}
      this.services.randomCall()
          .subscribe(
              res => {
                  o["loadedData"] = res["loadedData"];
                  this.cdRef.detectChanges();
              });
          )
   }
}

由于Thierry提到的this缺失，无论如何，手动更改检测都无法帮助您。

有关如何调用更改检测的更多选项，请参阅Triggering Angular2 change detection manually

Angular2通知变更模板

2 个答案: