Child routes and nested routing in Angular - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a child route inside the parent route.

Angular

const routes: Routes = [
  { path: 'parent', component: ParentComponent, children: [
    { path: [1], component: ChildComponent }
  ] }
];

Drag options to blanks, or click blank then click option'

A'child'

B'children'

C'parent-child'

D'child-route'

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'children' as the path string instead of the actual child route name.

Forgetting to put the path in quotes.

The child route path should be a string like 'child' to define the nested route under 'parent'.

2fill in blank

medium

Complete the code to import RouterModule with the routes in an Angular module.

Angular

@NgModule({
  imports: [RouterModule.[1](routes)],
  exports: [RouterModule]
})
export class AppRoutingModule {}

Drag options to blanks, or click blank then click option'

Asetup

BforRoot

Cconfigure

DforChild

Attempts:

3 left

💡 Hint

Common Mistakes

Using forChild in the root routing module.

Using a non-existent method like configure or setup.

Use forRoot to register the main routes in the root module.

3fill in blank

hard

Fix the error in the nested routes by completing the code correctly.

Angular

const routes: Routes = [
  { path: 'dashboard', component: DashboardComponent, [1]: [
    { path: 'stats', component: StatsComponent }
  ] }
];

Drag options to blanks, or click blank then click option'

Anested

Bchild

Cchildren

Dsubroutes

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'child' instead of 'children'.

Using 'nested' or 'subroutes' which are not valid properties.

The correct property to define nested routes is children.

4fill in blank

hard

Fill both blanks to create a nested route with a default child route.

Angular

const routes: Routes = [
  { path: 'account', component: AccountComponent, children: [
    { path: [1], component: ProfileComponent },
    { path: [2], redirectTo: 'profile', pathMatch: 'full' }
  ] }
];

Drag options to blanks, or click blank then click option'

A''

B'profile'

C'home'

D'default'

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'default' or 'home' instead of empty string for default path.

Redirecting to a path that does not exist.

The empty string '' defines the default child route path. The redirectTo points to 'profile' to load it by default.

5fill in blank

hard

Fill all three blanks to define nested routes with lazy loading and a child route.

Angular

const routes: Routes = [
  { path: 'settings', loadChildren: () => import('./settings/settings.module').[1](), children: [
    { path: [2], component: SettingsHomeComponent },
    { path: [3], component: SettingsDetailComponent }
  ] }
];

Drag options to blanks, or click blank then click option'

Athen

B''

C'detail'

Dload

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'load' instead of 'then' for lazy loading.

Wrong child route paths that don't match component purposes.

Use then to resolve the module import promise. The default child route path is empty string '', and the other child route is 'detail'.

Practice

1. What is the main purpose of child routes in Angular routing?

easy

A. To replace the main router outlet completely

B. To disable navigation between pages

C. To load components without URLs

D. To nest pages inside other pages for better organization

Solution

1. Step 1: Understand child routes concept

   Child routes allow nesting routes inside a parent route to organize pages hierarchically.

2. Step 2: Compare options with concept

   Only To nest pages inside other pages for better organization correctly describes this purpose; others are incorrect or unrelated.

3. Final Answer:

   To nest pages inside other pages for better organization -> Option D

4. Quick Check:

   Child routes = Nested pages [OK]

Hint: Child routes organize nested pages inside parents [OK]

Common Mistakes:

• Thinking child routes replace main router outlet
• Believing child routes work without URLs
• Confusing child routes with disabling navigation

2. Which syntax correctly defines a child route in Angular's RouterModule?

easy

A. { path: 'parent', children: ChildComponent }

B. { path: 'parent/child', component: ChildComponent }

C. { path: 'parent', children: [{ path: 'child', component: ChildComponent }] }

D. { path: 'parent', component: ParentComponent, child: [{ path: 'child' }] }

Solution

1. Step 1: Recall child route syntax

   Child routes are defined inside a 'children' array property of a route object.

2. Step 2: Match syntax with options

   { path: 'parent', children: [{ path: 'child', component: ChildComponent }] } correctly uses 'children' with an array of child route objects; others misuse properties or structure.

3. Final Answer:

   { path: 'parent', children: [{ path: 'child', component: ChildComponent }] } -> Option C

4. Quick Check:

   Child routes use 'children' array [OK]

Hint: Child routes go inside 'children' array in route config [OK]

Common Mistakes:

• Using 'child' instead of 'children'
• Defining child path as 'parent/child' in one route
• Assigning component directly to 'children'

3. Given this route config:

{ path: 'dashboard', component: DashboardComponent, children: [ { path: 'stats', component: StatsComponent } ] }

What happens when navigating to /dashboard/stats?

medium

A. Only StatsComponent loads, DashboardComponent is ignored

B. DashboardComponent loads with StatsComponent displayed inside its router-outlet

C. DashboardComponent loads but StatsComponent does not display

D. Navigation fails with an error

Solution

1. Step 1: Understand nested route rendering

   Child routes render their components inside the parent's <router-outlet>.

2. Step 2: Apply to given URL

   At /dashboard/stats, DashboardComponent loads first, then StatsComponent loads inside its router-outlet.

3. Final Answer:

   DashboardComponent loads with StatsComponent displayed inside its router-outlet -> Option B

4. Quick Check:

   Child route renders inside parent component [OK]

Hint: Child shows inside parent's router-outlet on nested URL [OK]

Common Mistakes:

• Expecting child component to replace parent
• Forgetting to add router-outlet in parent
• Assuming navigation error without cause

4. Identify the error in this route config:

{ path: 'home', component: HomeComponent, children: { path: 'profile', component: ProfileComponent } }

medium

A. 'children' should be an array, not an object

B. Missing component for 'home' route

C. 'path' cannot be used inside children

D. ProfileComponent must be declared in AppModule

Solution

1. Step 1: Check 'children' property type

   The 'children' property must be an array of route objects, not a single object.

2. Step 2: Verify given config

   Here, 'children' is incorrectly assigned an object instead of an array.

3. Final Answer:

   'children' should be an array, not an object -> Option A

4. Quick Check:

   'children' = array of routes [OK]

Hint: 'children' must always be an array, not a single object [OK]

Common Mistakes:

• Using object instead of array for children
• Confusing 'path' usage inside children
• Assuming missing component causes this error

5. You want to create a nested route where /settings loads SettingsComponent and /settings/profile loads ProfileComponent inside it. Which setup is correct?

hard

A. Define { path: 'settings', component: SettingsComponent, children: [{ path: 'profile', component: ProfileComponent }] } and add <router-outlet> in SettingsComponent template

B. Define { path: 'settings/profile', component: ProfileComponent } only, no children needed

C. Define { path: 'settings', component: ProfileComponent, children: [{ path: 'profile', component: SettingsComponent }] }

D. Define { path: 'settings', component: SettingsComponent } and load ProfileComponent manually inside SettingsComponent without routing

Solution

1. Step 1: Setup nested routes properly

   To nest ProfileComponent inside SettingsComponent, use 'children' array with ProfileComponent route.

2. Step 2: Ensure parent template has router-outlet

   SettingsComponent template must include <router-outlet> to display child routes.

3. Final Answer:

   Define { path: 'settings', component: SettingsComponent, children: [{ path: 'profile', component: ProfileComponent }] } and add <router-outlet> in SettingsComponent template -> Option A

4. Quick Check:

   Nested route + router-outlet = correct setup [OK]

Hint: Parent needs router-outlet and children array for nested routes [OK]

Common Mistakes:

• Defining nested path as one string without children
• Swapping parent and child components
• Not adding router-outlet in parent component