how to access Angular2 component specific data in

问题:

Is there any way to access Angular2 specific component specific data in console, for debugging purpose?

Like Angular1 has capability to access its components value in console.

回答1:

update 4.0.0

StackBlitz example

update RC.1

Plunker example In the browser console on the top-left (filter symbol) select plunkerPreviewTarget (or launch the demo app in its own window) then enter for example

Select a component in the DOM node and execute in the console

ng.probe($0);

or for IE - thanks to Kris Hollenbeck (see comments)

ng.probe(document.getElementById('myComponentId')).componentInstance

Alternative

Hint: enabling debug tools overrides ng.probe()

Enable debug tools like:

import {enableDebugTools} from '@angular/platform-browser';

bootstrap(App, []).then(appRef => enableDebugTools(appRef))

Use above Plunker example and in the console execute for example:

• ng.profiler.appRef
• ng.profiler.appRef._rootComponents[0].instance
• ng.profiler.appRef._rootComponents[0].hostView.internalView
• ng.profiler.appRef._rootComponents[0].hostView.internalView.viewChildren[0].viewChildren

I haven't found a way yet to investigate the Bar directive.

A better debug experience is provided by Augury which builds on this API

• https://augury.angular.io/
• https://www.youtube.com/watch?v=b1YV9vJKXEA

original (beta)

Here is a summary how to do that https://github.com/angular/angular/blob/master/TOOLS_JS.md (dead link and I haven't found a replacement).

Enabling debug tools

By default the debug tools are disabled. You can enable debug tools as follows:

import {enableDebugTools} from 'angular2/platform/browser';

bootstrap(Application).then((appRef) => {
  enableDebugTools(appRef);
});

Using debug tools

In the browser open the developer console (Ctrl + Shift + j in Chrome). The top level object is called ng and contains more specific tools inside it.

Example:

ng.profiler.timeChangeDetection();

See also

• Angular 2: How enable debugging in angular2 from browser console

回答2:

First select the element using chrome 'inspect element' and run below method in chrome 'developer console'.

ng.probe($0).componentInstance

You could also use a css selector as shown below.

ng.probe($$('.image-picker')[0]).componentInstance

If you do it often, to make it little easier, have a global shortcut created as below. Now select any DOM element inside the component using 'inspect element' and invoke 'e()' from console

window['e'] = () => eval('ng.probe($0).componentInstance');

回答3:

Using global scope variable.(any browser)

index.html

<script>
    var test;
</script>

on your component file

declare var test: any;

After ngOnInit() of that component file

For example

ngOnInit() {
   test = this;

}

Now we can access every variables and function of that component including services(imported on that component).

If you want to prevent accessing test for let's say production, you can conditionally give access to test like:

constructor(private _configService: ConfigService) {
}
ngOnInit() {
   if(_configService.prod) {
      test = this;
   }

}

Here _configService means the instance of service used by all components and services.
So variable would be set like:

export class ConfigService {
   prod = false;
}

回答4:

I'm surprised that no one has mentioned Augury here, it's a Chrome plugin that gives you convenient access to all the information in your components, and also makes it easier to see that information in the console directly:

https://augury.rangle.io/