Why Runtime cost of dynamic type resolution in C Sharp (C#)? - Purpose & Use Cases

The Big Idea

What if your program could decide the right action on the fly, but at what hidden cost?

The Scenario

Imagine you have a program that needs to handle many different types of objects, but you don't know their exact types until the program runs. You try to write code that checks each object's type manually and then calls the right method for it.

The Problem

This manual checking is slow and messy. Every time you add a new type, you must update your code. It's easy to make mistakes, and the program runs slower because it spends time figuring out types instead of doing useful work.

The Solution

Using dynamic type resolution lets the program automatically figure out the right method to call at runtime. This means cleaner code and less manual work, but it comes with a cost: the program spends extra time deciding which method to use while running.

Before vs After

✗ Before

if (obj is int) { HandleInt((int)obj); } else if (obj is string) { HandleString((string)obj); }

✓ After

dynamic d = obj; Handle(d);

What It Enables

This lets your program flexibly work with many types without rewriting code, making it easier to extend and maintain.

Real Life Example

Think of a drawing app that can handle circles, squares, and triangles. Instead of writing separate code for each shape, dynamic type resolution lets the app call the right drawing method automatically for any shape you add later.

Key Takeaways

Manual type checks are slow and error-prone.

Dynamic type resolution automates method selection at runtime.

This improves code flexibility but adds some runtime cost.