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+/* *******************************************************************************************
+ * ANGULAR CHEATSHEET
+ * DOCUMENTATION: https://angular.io/docs
+ * STYLE GUIDE: https://angular.io/guide/styleguide
+ * ******************************************************************************************* */
+
+```
+npm install --save @angular/cli       // declarative and flexible JavaScript framework for building UI
+ng serve                              // serve the app
+ng build                              // build the release
+```
+
+/* *******************************************************************************************
+ * Bootstrapping 
+ * ******************************************************************************************* */
+
+import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
+
+platformBrowserDynamic().bootstrapModule(AppModule); 
+// Bootstraps the app, using the root component from the specified NgModule.
+
+/* *******************************************************************************************
+ * NgModules 
+ * ******************************************************************************************* */
+import { NgModule } from '@angular/core';
+
+@NgModule({ declarations: ..., imports: ...,
+exports: ..., providers: ..., bootstrap: ...})
+class MyModule {} 
+// Defines a module that contains components, directives, pipes, and providers.
+
+declarations: [MyRedComponent, MyBlueComponent, MyDatePipe] 
+// List of components, directives, and pipes that belong to this module.
+
+imports: [BrowserModule, SomeOtherModule] 
+// List of modules to import into this module. Everything from the imported modules is available to declarations of this module.
+
+exports: [MyRedComponent, MyDatePipe] 
+// List of components, directives, and pipes visible to modules that import this module.
+
+providers: [MyService, { provide: ... }]  
+// List of dependency injection providers visible both to the contents of this module and to importers of this module.
+
+bootstrap: [MyAppComponent] 
+// List of components to bootstrap when this module is bootstrapped.
+
+
+/* *******************************************************************************************
+ * Template syntax 
+ * ******************************************************************************************* */
+
+// <input [value]="firstName"> 
+// Binds property value to the result of expression firstName.
+
+// <div [attr.role]="myAriaRole">  
+// Binds attribute role to the result of expression myAriaRole.
+
+// <div [class.extra-sparkle]="isDelightful">  
+// Binds the presence of the CSS class extra-sparkle on the element to the truthiness of the expression isDelightful.
+
+// <div [style.width.px]="mySize"> 
+// Binds style property width to the result of expression mySize in pixels. Units are optional.
+
+// <button (click)="readRainbow($event)">  
+// Calls method readRainbow when a click event is triggered on this button element (or its children) and passes in the event object.
+
+// <div title="Hello {{ponyName}}">  
+// Binds a property to an interpolated string, for example, "Hello Seabiscuit". Equivalent to: <div [title]="'Hello ' + ponyName">
+
+// <p>Hello {{ponyName}}</p> 
+// Binds text content to an interpolated string, for example, "Hello Seabiscuit".
+
+// <my-cmp [(title)]="name"> 
+// Sets up two-way data binding. Equivalent to: <my-cmp [title]="name" (titleChange)="name=$event">
+
+// <video #movieplayer ...>
+// <button (click)="movieplayer.play()">
+// </video>  
+// Creates a local variable movieplayer that provides access to the video element instance in data-binding and event-binding expressions in the current template.
+
+// <p *myUnless="myExpression">...</p> 
+// The * symbol turns the current element into an embedded template. Equivalent to: <ng-template [myUnless]="myExpression"><p>...</p></ng-template>
+
+// <p>Card No.: {{cardNumber | myCardNumberFormatter}}</p> 
+// Transforms the current value of expression cardNumber via the pipe called myCardNumberFormatter.
+
+// <p>Employer: {{employer?.companyName}}</p>  
+// The safe navigation operator (?) means that the employer field is optional and if undefined, the rest of the expression should be ignored.
+
+// <svg:rect x="0" y="0" width="100" height="100"/>  
+// An SVG snippet template needs an svg: prefix on its root element to disambiguate the SVG element from an HTML component.
+
+// <svg>
+// <rect x="0" y="0" width="100" height="100"/>
+// </svg>  
+// An <svg> root element is detected as an SVG element automatically, without the prefix.
+
+/* *******************************************************************************************
+ * Built-in directives
+ * ******************************************************************************************* */
+import { CommonModule } from '@angular/common';
+
+// // <section *ngIf="showSection"> 
+// // Removes or recreates a portion of the DOM tree based on the showSection expression.
+
+// <li *ngFor="let item of list">  
+// Turns the li element and its contents into a template, and uses that to instantiate a view for each item in list.
+
+// <div [ngSwitch]="conditionExpression">
+// <ng-template [ngSwitchCase]="case1Exp">...</ng-template>
+// <ng-template ngSwitchCase="case2LiteralString">...</ng-template>
+// <ng-template ngSwitchDefault>...</ng-template>
+// </div>  
+// Conditionally swaps the contents of the div by selecting one of the embedded templates based on the current value of conditionExpression.
+
+// <div [ngClass]="{'active': isActive, 'disabled': isDisabled}">  
+// Binds the presence of CSS classes on the element to the truthiness of the associated map values. The right-hand expression should return {class-name: true/false} map.
+
+// <div [ngStyle]="{'property': 'value'}">
+// <div [ngStyle]="dynamicStyles()"> 
+// Allows you to assign styles to an HTML element using CSS. You can use CSS directly, as in the first example, or you can call a method from the component.
+
+/* *******************************************************************************************
+ * Forms
+ * ******************************************************************************************* */
+
+import { FormsModule } from '@angular/forms';
+
+// <input [(ngModel)]="userName">  
+// Provides two-way data-binding, parsing, and validation for form controls.
+
+/* *******************************************************************************************
+ * Class decorators
+ * ******************************************************************************************* */
+
+import { Directive, ... } from '@angular/core';
+
+@Component({...})
+class MyComponent() {}  
+// Declares that a class is a component and provides metadata about the component.
+
+@Directive({...})
+class MyDirective() {}  
+// Declares that a class is a directive and provides metadata about the directive.
+
+@Pipe({...})
+class MyPipe() {} 
+// Declares that a class is a pipe and provides metadata about the pipe.
+
+@Injectable()
+class MyService() {}  
+// Declares that a class has dependencies that should be injected into the constructor when the dependency injector is creating an instance of this class.
+
+/* *******************************************************************************************
+ * Directive configuration
+ * ******************************************************************************************* */
+
+@Directive({ property1: value1, ... })
+
+selector: '.cool-button:not(a)' 
+// Specifies a CSS selector that identifies this directive within a template. Supported selectors include element, [attribute], .class, and :not().
+
+// Does not support parent-child relationship selectors.
+
+providers: [MyService, { provide: ... }]  
+// List of dependency injection providers for this directive and its children.
+
+/* *******************************************************************************************
+ * Component configuration
+ * ******************************************************************************************* */
+
+@Component extends @Directive, so the @Directive configuration applies to components as well
+
+moduleId: module.id 
+// If set, the templateUrl and styleUrl are resolved relative to the component.
+
+viewProviders: [MyService, { provide: ... }]  
+// List of dependency injection providers scoped to this component's view.
+
+template: 'Hello {{name}}'
+templateUrl: 'my-component.html'  
+// Inline template or external template URL of the component's view.
+
+styles: ['.primary {color: red}']
+styleUrls: ['my-component.css'] 
+// List of inline CSS styles or external stylesheet URLs for styling the component’s view.
+
+/* *******************************************************************************************
+ * Class field decorators for directives and components
+ * ******************************************************************************************* */
+
+import { Input, ... } from '@angular/core';
+
+@Input() myProperty;  
+// Declares an input property that you can update via property binding (example: <my-cmp [myProperty]="someExpression">).
+
+@Output() myEvent = new EventEmitter(); 
+// Declares an output property that fires events that you can subscribe to with an event binding (example: <my-cmp (myEvent)="doSomething()">).
+
+@HostBinding('class.valid') isValid;  
+// Binds a host element property (here, the CSS class valid) to a directive/component property (isValid).
+
+@HostListener('click', ['$event']) onClick(e) {...} 
+// Subscribes to a host element event (click) with a directive/component method (onClick), optionally passing an argument ($event).
+
+@ContentChild(myPredicate) myChildComponent;  
+// Binds the first result of the component content query (myPredicate) to a property (myChildComponent) of the class.
+
+@ContentChildren(myPredicate) myChildComponents;  
+// Binds the results of the component content query (myPredicate) to a property (myChildComponents) of the class.
+
+@ViewChild(myPredicate) myChildComponent; 
+// Binds the first result of the component view query (myPredicate) to a property (myChildComponent) of the class. Not available for directives.
+
+@ViewChildren(myPredicate) myChildComponents; 
+// Binds the results of the component view query (myPredicate) to a property (myChildComponents) of the class. Not available for directives.
+
+/* *******************************************************************************************
+ * Directive and component change detection and lifecycle hooks
+ * ******************************************************************************************* */
+
+// (implemented as class methods)
+
+constructor(myService: MyService, ...) { ... }  
+// Called before any other lifecycle hook. Use it to inject dependencies, but avoid any serious work here.
+
+ngOnChanges(changeRecord) { ... } 
+// Called after every change to input properties and before processing content or child views.
+
+ngOnInit() { ... }  
+// Called after the constructor, initializing input properties, and the first call to ngOnChanges.
+
+ngDoCheck() { ... } 
+// Called every time that the input properties of a component or a directive are checked. Use it to extend change detection by performing a custom check.
+
+ngAfterContentInit() { ... }  
+// Called after ngOnInit when the component's or directive's content has been initialized.
+
+ngAfterContentChecked() { ... } 
+// Called after every check of the component's or directive's content.
+
+ngAfterViewInit() { ... } 
+// Called after ngAfterContentInit when the component's views and child views / the view that a directive is in has been initialized.
+
+ngAfterViewChecked() { ... }  
+// Called after every check of the component's views and child views / the view that a directive is in.
+
+ngOnDestroy() { ... } 
+// Called once, before the instance is destroyed.
+
+/* *******************************************************************************************
+ * Dependency injection configuration
+ * ******************************************************************************************* */
+
+{ provide: MyService, useClass: MyMockService } 
+// Sets or overrides the provider for MyService to the MyMockService class.
+
+{ provide: MyService, useFactory: myFactory } 
+// Sets or overrides the provider for MyService to the myFactory factory function.
+
+{ provide: MyValue, useValue: 41 }  
+// Sets or overrides the provider for MyValue to the value 41.
+
+/* *******************************************************************************************
+ * Routing and navigation
+ * ******************************************************************************************* */
+
+import { Routes, RouterModule, ... } from '@angular/router';
+
+const routes: Routes = [
+{ path: '', component: HomeComponent },
+{ path: 'path/:routeParam', component: MyComponent },
+{ path: 'staticPath', component: ... },
+{ path: '**', component: ... },
+{ path: 'oldPath', redirectTo: '/staticPath' },
+{ path: ..., component: ..., data: { message: 'Custom' } }
+]);
+
+const routing = RouterModule.forRoot(routes); 
+// Configures routes for the application. Supports static, parameterized, redirect, and wildcard routes. Also supports custom route data and resolve.
+
+// <router-outlet></router-outlet>
+// <router-outlet name="aux"></router-outlet>
+// Marks the location to load the component of the active route.
+
+
+// <a routerLink="/path">
+// <a [routerLink]="[ '/path', routeParam ]">
+// <a [routerLink]="[ '/path', { matrixParam: 'value' } ]">
+// <a [routerLink]="[ '/path' ]" [queryParams]="{ page: 1 }">
+// <a [routerLink]="[ '/path' ]" fragment="anchor">
+// Creates a link to a different view based on a route instruction consisting of a route path, required and optional parameters, query parameters, and a fragment. To navigate to a root route, use the / prefix; for a child route, use the ./prefix; for a sibling or parent, use the ../ prefix.
+
+// <a [routerLink]="[ '/path' ]" routerLinkActive="active">  
+// The provided classes are added to the element when the routerLink becomes the current active route.
+
+class CanActivateGuard implements CanActivate {
+canActivate(
+route: ActivatedRouteSnapshot,
+state: RouterStateSnapshot
+): Observable<boolean>|Promise<boolean>|boolean { ... }
+}
+
+{ path: ..., canActivate: [CanActivateGuard] }  
+// An interface for defining a class that the router should call first to determine if it should activate this component. Should return a boolean or an Observable/Promise that resolves to a boolean.
+
+class CanDeactivateGuard implements CanDeactivate<T> {
+canDeactivate(
+component: T,
+route: ActivatedRouteSnapshot,
+state: RouterStateSnapshot
+): Observable<boolean>|Promise<boolean>|boolean { ... }
+}
+
+{ path: ..., canDeactivate: [CanDeactivateGuard] }  
+// An interface for defining a class that the router should call first to determine if it should deactivate this component after a navigation. Should return a boolean or an Observable/Promise that resolves to a boolean.
+
+class CanActivateChildGuard implements CanActivateChild {
+canActivateChild(
+route: ActivatedRouteSnapshot,
+state: RouterStateSnapshot
+): Observable<boolean>|Promise<boolean>|boolean { ... }
+}
+
+{ path: ..., canActivateChild: [CanActivateGuard],
+children: ... } 
+// An interface for defining a class that the router should call first to determine if it should activate the child route. Should return a boolean or an Observable/Promise that resolves to a boolean.
+
+class ResolveGuard implements Resolve<T> {
+resolve(
+route: ActivatedRouteSnapshot,
+state: RouterStateSnapshot
+): Observable<any>|Promise<any>|any { ... }
+}
+
+{ path: ..., resolve: [ResolveGuard] }  
+// An interface for defining a class that the router should call first to resolve route data before rendering the route. Should return a value or an Observable/Promise that resolves to a value.
+
+class CanLoadGuard implements CanLoad {
+canLoad(
+route: Route
+): Observable<boolean>|Promise<boolean>|boolean { ... }
+}
+
+{ path: ..., canLoad: [CanLoadGuard], loadChildren: ... } 
+// An interface for defining a class that the router should call first to check if the lazy loaded module should be loaded. Should return a boolean or an Observable/Promise that resolves to a boolean.
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