Given a service provided in providedIn: 'root' and also listed in a lazy-loaded module's providers array, what instance behavior occurs?
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Angular - Services and Dependency Injection
Given a service provided in providedIn: 'root' and also listed in a lazy-loaded module's providers array, what instance behavior occurs?
AOnly one instance is created app-wide from root scope.
BTwo instances are created: one root-wide and one for the lazy module.
CNo instance is created due to conflict.
DThe service is only available in the lazy-loaded module.
Step-by-Step Solution
Solution:
Step 1: Understand root and lazy module scopes
Providing a service in root creates a singleton app-wide instance. Providing it again in a lazy-loaded module creates a separate instance scoped to that module.
Step 2: Analyze instance count
Because the lazy module has its own provider, it overrides root for that module, resulting in two instances.
Final Answer:
Two instances are created: one root-wide and one for the lazy module. -> Option B
Quick Check:
Lazy module providers override root, creating separate instances [OK]
Quick Trick:Lazy module providers override root, creating separate instances [OK]
Common Mistakes:
MISTAKES
Assuming only one instance app-wide
Thinking no instance is created
Confusing lazy module scope with eager module
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