Yan Cui
I help clients go faster for less using serverless technologies.
This article is brought to you by
Don’t reinvent the patterns. Catalyst gives you consistent APIs for messaging, data, and workflow with key microservice patterns like circuit-breakers and retries for free.
Stumbled upon an interesting question on StackOverflow today regarding what goes on under the hood when you use the switch statement in C#.
Based on the answer by Brian Gideon (kudos for doing all that legwork!), for the following code:
public static int Main(string[] args)
{
switch (args[0])
{
case "1": return 1;
case "2": return 2;
case "3": return 3;
}
return 0;
}
the C# compiler will:
- if the number of case statements is small then emit a sequential equality comparison;
- if the number of case statements is large then emit a Dictionary lookup.
Also, on a related question regarding if-else vs. switch statement, the updated answer also seems to confirm this finding (regarding the use of a string in the switch statement at least) and Jon Skeet’s comment to the answer by ‘ima’ suggests that the threshold is 6 before the compiler decides to build a hash table, i.e. case statement count >= 7 then build dictionary.
Whenever you’re ready, here are 3 ways I can help you:
- Production-Ready Serverless: Join 20+ AWS Heroes & Community Builders and 1000+ other students in levelling up your serverless game. This is your one-stop shop for quickly levelling up your serverless skills.
- I help clients launch product ideas, improve their development processes and upskill their teams. If you’d like to work together, then let’s get in touch.
- Join my community on Discord, ask questions, and join the discussion on all things AWS and Serverless.