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@ -1,6 +1,5 @@
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include ../../../../_includes/_util-fns
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<!-- http://plnkr.co/edit/wg154K -->
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:marked
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We’ve all used a form to login, submit a help request, place an order, book a flight,
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schedule a meeting and perform countless other data entry tasks.
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@ -20,17 +19,17 @@ include ../../../../_includes/_util-fns
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- How to build an Angular form with a component and template
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- The `ng-model` two-way data binding syntax for reading and writing values to input controls
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- The `ngModel` two-way data binding syntax for reading and writing values to input controls
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- The `ng-control` directive to track the change state and validity of form controls
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- The `ngControl` directive to track the change state and validity of form controls
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- The special CSS classes that `ng-control` adds to form controls and how we can use them to provide strong visual feedback
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- The special CSS classes that `ngControl` adds to form controls and how we can use them to provide strong visual feedback
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- How to display validation errors to users and enable/disable form controls
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- How to share information across controls with template local variables
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[Live Example](/resources/live-examples/forms/ts/src/plnkr.html)
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[Live Example](/resources/live-examples/forms/ts/plnkr.html)
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.l-main-section
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:marked
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## Template-Driven Forms
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@ -51,7 +50,7 @@ include ../../../../_includes/_util-fns
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We'll discuss and learn to build the following template-driven form:
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figure.image-display
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img(src="/resources/images/devguide/forms/hf-1.png" width="400px" alt="Clean Form")
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img(src="/resources/images/devguide/forms/heroForm-1.png" width="400px" alt="Clean Form")
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:marked
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Here at the *Hero Employment Agency* we use this form to maintain personal information about the
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@ -62,7 +61,7 @@ figure.image-display
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If we delete the hero name, the form displays a validation error in an attention grabbing style:
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figure.image-display
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img(src="/resources/images/devguide/forms/hf-2.png" width="400px" alt="Invalid, Name Required")
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img(src="/resources/images/devguide/forms/heroForm-2.png" width="400px" alt="Invalid, Name Required")
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:marked
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Note that the submit button is disabled and the "required" bar to the left of the input control changed from green to red.
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@ -76,11 +75,11 @@ figure.image-display
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1. Create the `Hero` model class
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1. Create the component that controls the form
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1. Create a template with the initial form layout
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1. Add the **ng-model** directive to each form input control
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1. Add the **ng-control** directive to each form input control
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1. Add the **ngModel** directive to each form input control
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1. Add the **ngControl** directive to each form input control
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1. Add custom CSS to provide visual feedback
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1. Show and hide validation error messages
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1. Handle form submission with **ng-submit**
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1. Handle form submission with **ngSubmit**
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1. Disable the form’s submit button until the form is valid
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:marked
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@ -98,7 +97,7 @@ figure.image-display
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Create a new file in the app folder called `hero.ts` and give it the following class definition:
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+makeExample('forms/ts/src/app/hero.ts', null, 'app/hero.ts')
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+makeExample('forms/ts/app/hero.ts', null, 'app/hero.ts')
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:marked
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It's an anemic model with few requirements and no behavior. Perfect for our demo.
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@ -109,10 +108,11 @@ figure.image-display
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The `alterEgo` is optional and the constructor lets us omit it; note the (?) in `alterEgo?`.
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We can create a new hero like this:
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```
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let myHero = new Hero(42, 'SkyDog', 'Fetch any object at any distance', 'Leslie Rollover');
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code-example(format="").
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let myHero = new Hero(42, 'SkyDog',
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'Fetch any object at any distance', 'Leslie Rollover');
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console.log('My hero is called ' + myHero.name); // "My hero is called SkyDog"
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```
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:marked
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.l-main-section
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:marked
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@ -124,7 +124,7 @@ figure.image-display
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Create a new file called `hero-form.component.ts` and give it the following definition:
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+makeExample('forms/ts/src/app/hero-form.component.ts', 'first', 'app/hero-form.component.ts')
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+makeExample('forms/ts/app/hero-form.component.ts', 'first', 'app/hero-form.component.ts')
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:marked
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There’s nothing special about this component, nothing form-specific, nothing to distinguish it from any component we've written before.
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@ -155,16 +155,16 @@ figure.image-display
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We made a good choice to put the HTML template elsewhere.
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We'll write that template in a moment. Before we do, we'll take a step back
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and revise the `app.ts` to make use of our new `HeroFormComponent`.
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and revise the `app.component.ts` to make use of our new `HeroFormComponent`.
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.l-main-section
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:marked
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## Revise the *app.ts*
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## Revise the *app.component.ts*
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`app.ts` is the application's root component. It will host our new `HeroFormComponent`.
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`app.component.ts` is the application's root component. It will host our new `HeroFormComponent`.
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Replace the contents of the "QuickStart" version with the following:
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+makeExample('forms/ts/src/app/app.ts', null, 'app/app.ts')
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+makeExample('forms/ts/app/app.component.ts', null, 'app/app.component.ts')
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:marked
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.l-sub-section
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@ -184,7 +184,7 @@ figure.image-display
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Create a new template file called `hero-form.component.html` and give it the following definition:
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+makeExample('forms/ts/src/app/hero-form.component.html', 'start', 'app/hero-form.component.html')
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+makeExample('forms/ts/app/hero-form.component.html', 'start', 'app/hero-form.component.html')
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:marked
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|
That is plain old HTML 5. We're presenting two of the `Hero` fields, `name` and `alterEgo`, and
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@ -213,15 +213,15 @@ figure.image-display
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Let's add the stylesheet.
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ol
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|
li Open a terminal window and enter the command:
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|
|
li Open a terminal window in the application root folder and enter the command:
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|
|
code-example(language="html" escape="html").
|
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|
npm install bootstrap --save
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|
|
li Open <code>index.html</code> and add the following link to the <code><head></code>.
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|
+makeExample('forms/ts/src/index.html', 'bootstrap')(format=".")
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+makeExample('forms/ts/index.html', 'bootstrap')(format=".")
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|
:marked
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|
.l-main-section
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|
:marked
|
|
|
|
|
## Add Powers with ***ng-for**
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|
|
## Add Powers with ***ngFor**
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|
|
Our hero may choose one super power from a fixed list of Agency-approved powers.
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|
We maintain that list internally (in `HeroFormComponent`).
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|
@ -230,7 +230,7 @@ ol
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a technique we might have seen before in the [Displaying Data](./displaying-data.html) chapter.
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|
|
Add the following HTML *immediately below* the *Alter Ego* group.
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|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'powers', 'app/hero-form.component.html (excerpt)')
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|
+makeExample('forms/ts/app/hero-form.component.html', 'powers', 'app/hero-form.component.html (excerpt)')(format=".")
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|
:marked
|
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|
|
We are repeating the `<options>` tag for each power in the list of Powers.
|
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|
|
@ -239,11 +239,11 @@ ol
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|
.l-main-section
|
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|
|
:marked
|
|
|
|
|
## Two-way data binding with ***ng-model**
|
|
|
|
|
## Two-way data binding with ***ngModel**
|
|
|
|
|
Running the app right now would be disappointing.
|
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|
|
|
|
|
|
|
|
figure.image-display
|
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|
|
|
img(src="/resources/images/devguide/forms/hf-3.png" width="400px" alt="Early form with no binding")
|
|
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|
|
img(src="/resources/images/devguide/forms/heroForm-3.png" width="400px" alt="Early form with no binding")
|
|
|
|
|
:marked
|
|
|
|
|
We don't see hero data because we are not binding to the `Hero` yet.
|
|
|
|
|
We know how to do that from earlier chapters.
|
|
|
|
@ -259,7 +259,7 @@ figure.image-display
|
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|
|
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|
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|
|
Find the `<input>` tag for the "Name" and update it like this
|
|
|
|
|
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'ng-model-1')
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.html', 'ngModel-1','app/hero-form.component.html (excerpt)')(format=".")
|
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|
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|
.l-sub-section
|
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|
|
:marked
|
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|
@ -268,42 +268,42 @@ figure.image-display
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|
We left ourselves a note to throw it way when we're done.
|
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|
|
|
|
|
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|
|
:marked
|
|
|
|
|
Focus on the binding syntax: `[(ng-model)]="..."`.
|
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|
|
|
Focus on the binding syntax: `[(ngModel)]="..."`.
|
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|
|
|
|
|
|
|
|
If we ran the app right now and started typing in the *Name* input box,
|
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|
|
adding and deleting characters, we'd see them appearing and disappearing
|
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|
|
from the interpolated text.
|
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|
|
|
At some point it might look like this.
|
|
|
|
|
figure.image-display
|
|
|
|
|
img(src="/resources/images/devguide/forms/ng-model-in-action.png" width="400px" alt="ng-model in action")
|
|
|
|
|
img(src="/resources/images/devguide/forms/ng-model-in-action.png" width="400px" alt="ngModel in action")
|
|
|
|
|
:marked
|
|
|
|
|
The diagnostic is evidence that we really are flowing values from the input box to the model and
|
|
|
|
|
back again. **That's two-way data binding!**
|
|
|
|
|
|
|
|
|
|
Let's add similar `[(ng-model)]` bindings to *Alter Ego* and *Hero Power*.
|
|
|
|
|
Let's add similar `[(ngModel)]` bindings to *Alter Ego* and *Hero Power*.
|
|
|
|
|
We'll ditch the input box binding message
|
|
|
|
|
and add a new binding at the top to the component's `diagnostic` property.
|
|
|
|
|
Then we can confirm that two-way data binding works *for the entire Hero model*.
|
|
|
|
|
|
|
|
|
|
After revision the core of our form should have three `[(ng-model)]` bindings that
|
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|
|
After revision the core of our form should have three `[(ngModel)]` bindings that
|
|
|
|
|
look much like this:
|
|
|
|
|
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'ng-model-2', 'app/hero-form.component.html (excerpt)')
|
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|
|
+makeExample('forms/ts/app/hero-form.component.html', 'ngModel-2', 'app/hero-form.component.html (excerpt)')
|
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|
|
|
|
|
|
|
|
:marked
|
|
|
|
|
If we ran the app right now and changed every Hero model property, the form might display like this:
|
|
|
|
|
figure.image-display
|
|
|
|
|
img(src="/resources/images/devguide/forms/ng-model-in-action-2.png" width="400px" alt="ng-model in super action")
|
|
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|
|
img(src="/resources/images/devguide/forms/ng-model-in-action-2.png" width="400px" alt="ngModel in super action")
|
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|
|
|
:marked
|
|
|
|
|
The diagnostic near the top of the form
|
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|
|
|
confirms that all of our changes are reflected in the model.
|
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|
|
|
|
|
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|
|
** We're done with the diagnostic binding. Delete it now.**
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|
|
**Delete** the `{{diagnostic}}` binding at the top as it has served its purpose.
|
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|
|
|
|
|
|
.l-sub-section
|
|
|
|
|
:marked
|
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|
|
|
### Inside [(ng-model)]
|
|
|
|
|
*This section is an optional deep dive into [(ng-model)]. Not interested? Skip ahead!*
|
|
|
|
|
### Inside [(ngModel)]
|
|
|
|
|
*This section is an optional deep dive into [(ngModel)]. Not interested? Skip ahead!*
|
|
|
|
|
|
|
|
|
|
The punctuation in the binding syntax, <span style="font-family:courier"><b>[()]</b></span>, is a good clue to what's going on.
|
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|
|
|
|
|
|
|
@ -320,23 +320,23 @@ figure.image-display
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|
In fact, we can break the `NgModel` binding into its two separate modes
|
|
|
|
|
as we do in this re-write of the "Name" `<input>` binding:
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'ng-model-3')
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.html', 'ngModel-3','app/hero-form.component.html (excerpt)')(format=".")
|
|
|
|
|
|
|
|
|
|
:marked
|
|
|
|
|
<br>The Property Binding should feel familiar. The Event Binding might seem strange.
|
|
|
|
|
|
|
|
|
|
The `ng-model-change` is not an `<input>` element event.
|
|
|
|
|
The `ngModelChange` is not an `<input>` element event.
|
|
|
|
|
It is actually an event property of the `NgModel` directive.
|
|
|
|
|
When Angular sees a binding target in the form <span style="font-family:courier">[(abc)]</span>,
|
|
|
|
|
it expects the `abc` directive to have an `abc` input property and an `abc-change` output property.
|
|
|
|
|
|
|
|
|
|
The other oddity is the template expression, `model.name = $event`.
|
|
|
|
|
We're used to seeing an `$event` object coming from a DOM event.
|
|
|
|
|
The `ng-model-change` property doesn't produce a DOM event; it's an Angular `EventEmitter`
|
|
|
|
|
The `ngModelChange` property doesn't produce a DOM event; it's an Angular `EventEmitter`
|
|
|
|
|
property that returns the input box value when it fires — which is precisely what
|
|
|
|
|
we should assign to the model's `name' property.
|
|
|
|
|
|
|
|
|
|
Nice to know but is it practical? We almost always prefer `[(ng-model)]`.
|
|
|
|
|
Nice to know but is it practical? We almost always prefer `[(ngModel)]`.
|
|
|
|
|
We might split the binding if we had to do something special in
|
|
|
|
|
the event handling such as debounce or throttle the key strokes.
|
|
|
|
|
|
|
|
|
@ -345,7 +345,7 @@ figure.image-display
|
|
|
|
|
|
|
|
|
|
.l-main-section
|
|
|
|
|
:marked
|
|
|
|
|
## Track change-state and validity with **ng-control**
|
|
|
|
|
## Track change-state and validity with **ngControl**
|
|
|
|
|
|
|
|
|
|
A form isn't just about data binding. We'd also like to know the state of the controls on our form.
|
|
|
|
|
The `NgControl` directive keeps track of control state for us.
|
|
|
|
@ -365,18 +365,18 @@ figure.image-display
|
|
|
|
|
control and make messages appear or disappear.
|
|
|
|
|
|
|
|
|
|
We'll explore those effects soon. Right now
|
|
|
|
|
we should **add `ng-control`to all three form controls**,
|
|
|
|
|
we should **add `ngControl`to all three form controls**,
|
|
|
|
|
starting with the *Name* input box
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'ng-control-1', 'app/hero-form.component.html (excerpt)')
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.html', 'ngControl-1', 'app/hero-form.component.html (excerpt)')(format=".")
|
|
|
|
|
:marked
|
|
|
|
|
Be sure to assign a unique name to each `ng-control` directive.
|
|
|
|
|
Be sure to assign a unique name to each `ngControl` directive.
|
|
|
|
|
|
|
|
|
|
.l-sub-section
|
|
|
|
|
:marked
|
|
|
|
|
Angular registers controls under their `ng-control` names
|
|
|
|
|
Angular registers controls under their `ngControl` names
|
|
|
|
|
with the `NgForm`.
|
|
|
|
|
We didn't add the `NgForm` directive explicitly but it's here
|
|
|
|
|
and we'll talk about it [later in this chapter](#ng-form).
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and we'll talk about it [later in this chapter](#ngForm).
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.l-main-section
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:marked
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@ -406,7 +406,7 @@ table
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Let's add a temporary [local template variable](./template-syntax.html#local-vars) named **spy**
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to the "Name" `<input>` tag and use the spy to display those classes.
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+makeExample('forms/ts/src/app/hero-form.component.html', 'ng-control-2')
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+makeExample('forms/ts/app/hero-form.component.html', 'ngControl-2','app/hero-form.component.html (excerpt)')(format=".")
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:marked
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Now run the app and focus on the *Name* input box.
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@ -438,12 +438,12 @@ figure.image-display
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We achieve this effect by adding two styles to a new `styles.css` file
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that we add to our project as a sibling to `index.html`.
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+makeExample('forms/ts/src/styles.css',null,'styles.css')
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+makeExample('forms/ts/styles.css',null,'styles.css')(format=".")
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:marked
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These styles select for the two Angular validity classes and the HTML 5 "required" attribute.
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We update the `<head>` of the `index.html` to include this style sheet.
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+makeExample('forms/ts/src/index.html', 'styles', 'index.html (excerpt)')(format=".")
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+makeExample('forms/ts/index.html', 'styles', 'index.html (excerpt)')(format=".")
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:marked
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## Show and Hide Validation Error messages
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@ -464,39 +464,36 @@ figure.image-display
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Here's how we do it for the *name* input box:
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-var stylePattern = { otl: /(#name="form")|(.*div.*$)|(Name is required)/gm };
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+makeExample('forms/ts/src/app/hero-form.component.html',
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+makeExample('forms/ts/app/hero-form.component.html',
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'name-with-error-msg',
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'app/hero-form.component.html (excerpt)',
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stylePattern)
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:marked
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We initialized the template local variable with the word "form" (`#name="form"`)
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When we added the `ngControl` directive, we bound it to the the model's `name` property.
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Here we initialize a template local variable (`name`) with the value "ngForm" (`#name="ngForm"`).
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Angular recognizes that syntax and re-sets the `name` local template variable to the
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`ngControl` directive instance.
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In other words, the `name` local template variable becomes a handle on the `ngControl` object
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for this input box.
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Angular recognizes that syntax and sets the `name` variable
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to the `Control` object identified by the `ng-control` directive which,
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not coincidentally, we called "name".
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We bind the `Control` object's `valid` property to the element's `hidden` property.
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While the control is valid, the message is hidden;
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if it becomes invalid, the message is revealed.
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<a id="ng-form"></a>
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Now we can control visibility of the "name" error message by binding the message `<div>` element's `hidden` property
|
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to the `ngControl` object's `valid` property. The message is hidden while the control is valid;
|
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the message is revealed when the control becomes invalid.
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<a id="ngForm"></a>
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|
.l-sub-section
|
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:marked
|
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|
### The NgForm directive
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Recall from the previous section that `ng-control` registered this input box with the
|
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`NgForm` directive as "name".
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We didn't add the **[`NgForm`](../api/core/NgForm-class.html) directive** explicitly.
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We just set a template local variable with the value of an `NgForm` directive.
|
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|
Why did that work? We didn't add the **[`NgForm`](../api/core/NgForm-class.html) directive** explicitly.
|
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Angular added it surreptiously, wrapping it around the `<form>` element
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The `NgForm` directive supplements the `form` element with additional features.
|
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|
It collects `Controls` (elements identified by an `ng-control` directive)
|
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|
|
It collects `Controls` (elements identified by an `ngControl` directive)
|
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|
|
and monitors their properties including their validity.
|
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|
|
It has its own `valid` property which is true only if every contained
|
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|
|
It also has its own `valid` property which is true only if every contained
|
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|
control is valid.
|
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|
|
In this example, we are pulling the "name" control out of its `controls` collection
|
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|
|
and assigning it to the template local variable so that we can
|
|
|
|
|
access the control's properties — such as the control's own `valid` property.
|
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|
|
:marked
|
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|
|
The Hero *Alter Ego* is optional so we can leave that be.
|
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|
|
@ -507,35 +504,32 @@ figure.image-display
|
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|
|
.l-main-section
|
|
|
|
|
:marked
|
|
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|
|
## Submit the form with **ng-submit**
|
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|
|
|
## Submit the form with **ngSubmit**
|
|
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|
|
The user should be able to submit this form after filling it in.
|
|
|
|
|
The Submit button at the bottom of the form
|
|
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|
|
does nothing on its own but it will
|
|
|
|
|
trigger a form submit because of its type (`type="submit"`).
|
|
|
|
|
|
|
|
|
|
A "form submit" is meaningless at the moment.
|
|
|
|
|
To make it meaningful, we'll update the `<form>` tag with another Angular directive, `NgSubmit`,
|
|
|
|
|
and bind it to our `HeroFormComponent.submit()` method with an EventBinding
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'ng-submit')(format=".")
|
|
|
|
|
A "form submit" is useless at the moment.
|
|
|
|
|
To make it useful, we'll update the `<form>` tag with another Angular directive, `NgSubmit`,
|
|
|
|
|
and bind it to the `HeroFormComponent.submit()` method with an event binding
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.html', 'ngSubmit')(format=".")
|
|
|
|
|
|
|
|
|
|
:marked
|
|
|
|
|
We slipped in something extra there at the end! We defined a
|
|
|
|
|
template local variable, **`#hf`**, and initialized it with the value, "form".
|
|
|
|
|
template local variable, **`#heroForm`**, and initialized it with the value, "ngForm".
|
|
|
|
|
|
|
|
|
|
The variable `hf` is now a handle to the `NgForm` as we [discussed earlier](#ng-form)
|
|
|
|
|
with respect to `ng-control` although this time we have a reference to the form
|
|
|
|
|
rather than a control.
|
|
|
|
|
The variable `heroForm` is now a handle to the `NgForm` directive that we [discussed earlier](#ngForm)
|
|
|
|
|
This time `heroForm` remains a reference to the form as a whole.
|
|
|
|
|
|
|
|
|
|
We'll bind the Form's over-all validity via
|
|
|
|
|
the `hf` variable to the button's `disabled` property
|
|
|
|
|
using an Event Binding. Here's the code:
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'submit-button')
|
|
|
|
|
Later in the template we bind the button's `disabled` property to the form's over-all validity via
|
|
|
|
|
the `heroForm` variable. Here's that bit of markup:
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.html', 'submit-button')
|
|
|
|
|
:marked
|
|
|
|
|
If we run the application now, we find that the button is enabled.
|
|
|
|
|
It doesn't do anything useful yet but it's alive.
|
|
|
|
|
Re-run the application. The form opens in a valid state and the button is enabled.
|
|
|
|
|
|
|
|
|
|
Now if we delete the *Name*, we violate the "required" rule which
|
|
|
|
|
is duely noted in our error message. The Submit button is also disabled.
|
|
|
|
|
Now delete the *Name*. We violate the "name required" rule which
|
|
|
|
|
is duely noted in our error message as before. And now the Submit button is also disabled.
|
|
|
|
|
|
|
|
|
|
Not impressed? Think about it for a moment. What would we have to do to
|
|
|
|
|
wire the button's enable/disabled state to the form's validity without Angular's help?
|
|
|
|
@ -563,14 +557,14 @@ figure.image-display
|
|
|
|
|
Start by wrapping the form in a `<div>` and bind
|
|
|
|
|
its `hidden` property to the `HeroFormComponent.submitted` property.
|
|
|
|
|
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'edit-div', 'app/hero-form.component.html (excerpt)')
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.html', 'edit-div', 'app/hero-form.component.html (excerpt)')(format=".")
|
|
|
|
|
|
|
|
|
|
:marked
|
|
|
|
|
The main form is visible from the start because the
|
|
|
|
|
the `submitted` property is false until we submit the form,
|
|
|
|
|
as this fragment from the `HeroFormComponent` reminds us:
|
|
|
|
|
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.ts', 'submitted')
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.ts', 'submitted')(format=".")
|
|
|
|
|
|
|
|
|
|
:marked
|
|
|
|
|
When we click the Submit button, the `submitted` flag becomes true and the form disappears
|
|
|
|
@ -578,7 +572,7 @@ figure.image-display
|
|
|
|
|
|
|
|
|
|
Now we need to show something else while the form is in the submitted state.
|
|
|
|
|
Add the following block of HTML below the `<div>` wrapper we just wrote:
|
|
|
|
|
+makeExample('forms/ts/src/app/hero-form.component.html', 'submitted', 'app/hero-form.component.html (excerpt)')
|
|
|
|
|
+makeExample('forms/ts/app/hero-form.component.html', 'submitted', 'app/hero-form.component.html (excerpt)')
|
|
|
|
|
|
|
|
|
|
:marked
|
|
|
|
|
There's our hero again, displayed read-only with interpolation bindings.
|
|
|
|
@ -599,43 +593,45 @@ figure.image-display
|
|
|
|
|
|
|
|
|
|
- An Angular HTML form template.
|
|
|
|
|
- A form component class with a `Component` decorator.
|
|
|
|
|
- The `ng-submit` directive for handling the form submission.
|
|
|
|
|
- Template local variables such as `#hf`, `#name`, `#alter-ego` and `#power`.
|
|
|
|
|
- The `ng-model` directive for two-way data binding.
|
|
|
|
|
- The `ng-control` for validation and form element change tracking.
|
|
|
|
|
- The `ngSubmit` directive for handling the form submission.
|
|
|
|
|
- Template local variables such as `#heroForm`, `#name`, `#alter-ego` and `#power`.
|
|
|
|
|
- The `ngModel` directive for two-way data binding.
|
|
|
|
|
- The `ngControl` for validation and form element change tracking.
|
|
|
|
|
- The local variable’s `valid` property on input controls to check if a control is valid and show/hide error messages.
|
|
|
|
|
- Property Binding to disable the submit button when the form is invalid.
|
|
|
|
|
- Custom CSS classes that provide visual feedback to users about required invalid controls.
|
|
|
|
|
- Controlling the submit button's enabled state by binding to `NgForm` validity.
|
|
|
|
|
- Custom CSS classes that provide visual feedback to users about invalid controls.
|
|
|
|
|
|
|
|
|
|
Here’s the final version of the application:
|
|
|
|
|
|
|
|
|
|
+makeTabs(
|
|
|
|
|
`forms/ts/src/app/hero-form.component.html,
|
|
|
|
|
forms/ts/src/app/hero-form.component.ts,
|
|
|
|
|
forms/ts/src/app/hero.ts,
|
|
|
|
|
forms/ts/src/app/app.ts,
|
|
|
|
|
forms/ts/src/index.html,
|
|
|
|
|
forms/ts/src/styles.css`,
|
|
|
|
|
'final, final,,,,',
|
|
|
|
|
`hero-form.component.html,
|
|
|
|
|
hero-form.component.ts,
|
|
|
|
|
hero.ts,
|
|
|
|
|
app.ts,
|
|
|
|
|
index.html,
|
|
|
|
|
styles.css`)
|
|
|
|
|
:marked
|
|
|
|
|
Our final project folder structure should look like this:
|
|
|
|
|
```
|
|
|
|
|
code-example(format="").
|
|
|
|
|
angular2-forms
|
|
|
|
|
├── node_modules
|
|
|
|
|
├── src
|
|
|
|
|
│ ├── app
|
|
|
|
|
│ | ├── app.ts
|
|
|
|
|
│ | ├── hero.ts
|
|
|
|
|
│ | ├── hero-form.component.html
|
|
|
|
|
│ | └── hero-form.component.ts
|
|
|
|
|
│ ├── index.html
|
|
|
|
|
│ ├── styles.css
|
|
|
|
|
│ └── tsconfig.json
|
|
|
|
|
├── app
|
|
|
|
|
| ├── app.component.ts
|
|
|
|
|
| ├── boot.ts
|
|
|
|
|
| ├── hero.ts
|
|
|
|
|
| ├── hero-form.component.html
|
|
|
|
|
| └── hero-form.component.ts
|
|
|
|
|
├── index.html
|
|
|
|
|
├── styles.css
|
|
|
|
|
├── tsconfig.json
|
|
|
|
|
└── package.json
|
|
|
|
|
```
|
|
|
|
|
:marked
|
|
|
|
|
Here’s the final version of the source:
|
|
|
|
|
|
|
|
|
|
+makeTabs(
|
|
|
|
|
`forms/ts/app/hero-form.component.ts,
|
|
|
|
|
forms/ts/app/hero-form.component.html,
|
|
|
|
|
forms/ts/app/hero.ts,
|
|
|
|
|
forms/ts/app/app.component.ts,
|
|
|
|
|
forms/ts/app/boot.ts,
|
|
|
|
|
forms/ts/index.html,
|
|
|
|
|
forms/ts/styles.css`,
|
|
|
|
|
'final, final,,,,,',
|
|
|
|
|
`hero-form.component.ts,
|
|
|
|
|
hero-form.component.html,
|
|
|
|
|
hero.ts,
|
|
|
|
|
app.component.ts,
|
|
|
|
|
boot.ts,
|
|
|
|
|
index.html,
|
|
|
|
|
styles.css`)
|
|
|
|
|
:marked
|