Runtime cost of dynamic type resolution in C Sharp (C#) - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is dynamic type resolution in C#?

Dynamic type resolution is when the program determines the type of an object at runtime instead of compile time, allowing more flexible code but with some performance cost.

beginner

Why does dynamic type resolution have a runtime cost?

Because the program must look up the actual type and method to call during execution, which takes extra time compared to compile-time type checking.

intermediate

How does C# implement dynamic type resolution internally?

C# uses the Dynamic Language Runtime (DLR) which performs method binding and type checks at runtime using reflection and caching to improve performance.

intermediate

What is a common performance impact of using 'dynamic' in C#?

Using 'dynamic' can slow down method calls because the runtime must resolve the method to invoke each time, unlike static calls which are direct.

advanced

How can you reduce the runtime cost of dynamic type resolution?

You can cache dynamic call sites or avoid excessive use of 'dynamic' in performance-critical code to reduce overhead.

What does dynamic type resolution mean in C#?

A Using only static types

B Determining object type at compile time

C Ignoring object types

D Determining object type at runtime

Dynamic type resolution means the program figures out the object's type while running, not before.

Which C# feature enables dynamic type resolution?

A const keyword

B dynamic keyword

C var keyword

D readonly keyword

The 'dynamic' keyword tells C# to resolve types at runtime.

What is a main cause of runtime cost when using dynamic types?

A Compile-time optimization

B Static type checking

C Runtime method lookup

D Memory allocation only

The runtime must find the correct method to call, which takes extra time.

Which runtime component helps with dynamic type resolution in C#?

A Dynamic Language Runtime (DLR)

B Common Language Runtime (CLR)

C Just-In-Time compiler (JIT)

D Garbage Collector (GC)

The DLR manages dynamic operations and type resolution.

How can you improve performance when using dynamic types?

A Cache dynamic call sites

B Use more dynamic variables

C Avoid static typing

D Disable runtime checks

Caching reduces repeated runtime lookups, improving speed.

Explain what runtime cost means in the context of dynamic type resolution in C#.

Think about what happens when the program decides types while running.

Describe ways to reduce the performance cost when using dynamic types in C#.

Consider how to avoid repeated work at runtime.