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WeAreDevelopers LIVE • Oct 16, 2024

Tips, tricks and quirks in .NET

Paweł Łukaszuk

Did you know blindly following IDE refactoring suggestions can make your .NET code five times slower? Look beneath the syntax to uncover C#'s most surprising performance quirks.

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#1 about 5 min

Data types and list implementation in .NET

How the default generic list in .NET is essentially a resizable array with a small default size.

#2 about 4 min

Performance differences between for and foreach loops

Analyzing why for loops historically outperform foreach loops and how .NET 7 optimizes this gap.

#3 about 5 min

Performance comparison of Count and Where in LINQ

Uncovering why filtering collections using Count with a predicate is slower than using Where followed by Count.

#4 about 5 min

StringBuilder versus string concatenation operator performance

Comparing string joining methods to show when standard operator concatenation outperforms StringBuilder operations.

#5 about 3 min

Comparing String.Empty to empty string literals

Examining intermediate code to reveal that String.Empty and empty string literals perform identically.

#6 about 5 min

Operator overloading and null checking vulnerabilities in C#

The risks of relying on legacy equality operators for null checking and how to properly validate objects.

#7 about 4 min

Bypassing try-catch exception handling using Environment.FailFast

Using the Environment.FailFast method to instantly kill an application without triggering standard exception handling.

#8 about 5 min

Understanding banker's rounding behavior in Math.Round

Exploring how the default Math.Round function balances distribution by rounding halves to the nearest even number.

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