Edge cases in the string vs. String comparison in C#

Yan Cui

I help clients go faster for less using serverless technologies.

This article is brought to you by

The real-time data platform that empowers developers to build innovative products faster and more reliably than ever before.

Learn more

Whilst most C# developer would know that in C# the string type is equivalent to the System.String type because string is simply an alias for the System.String type. There are other framework defined alias like string, such as int for System.Int32 and long for System.Int64.

Whilst in normal usage the two are identical, thanks to Marc Gravell’s answer here, I found out about two interesting edge cases:

  • you need a  using System; to use String, you don’t for string
  • if you define a local class String { }, then String refers to that class, you can’t define a class called string

On a related topic, one thing that’s always been curious to me is that there are no ToInt or ToLong methods in the Convert class but only ToIn32 and ToInt64. Dan Puzey gave me a plausible explanation for this though:

Convert is a framework class, not a language keyword. If it had methods named after the C# keywords, the methods would make no sense in VB or F# or other .NET languages.

Whenever you’re ready, here are 4 ways I can help you:

  1. 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.
  2. Do you want to know how to test serverless architectures with a fast dev & test loop? Check out my latest course, Testing Serverless Architectures and learn the smart way to test serverless.
  3. 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.
  4. Join my community on Discord, ask questions, and join the discussion on all things AWS and Serverless.

Leave a Comment

Your email address will not be published. Required fields are marked *