For versus Foreach Performance
The lesson contrasts the indexed for loop with the foreach keyword, then dives into how foreach compiles into an enumerator object with MoveNext and Current, explaining that enumerators are designed for sequentially traversing potentially infinite or memory-unfriendly data structures such as database result sets. We establish that enumerator overhead makes foreach significantly slower than for on in-memory collections.
Previous Module
Basic Performance Optimizations
This Module
Array Performance Optimizations
1D, 2D and Jagged Arrays
1D Arrays in Intermediate Language
2D Arrays in Intermediate Language
Jagged Arrays in Intermediate Language
Demo: Benchmarking Arrays (part 1)
Demo: Benchmarking Arrays (part 2)
Array Performance Recap
For versus Foreach Performance
Foreach on an Array
Demo: Benchmarking For and Foreach
Demo: For and Foreach in Intermediate Language