LINQ为什么要更快？它还在内部使用循环。大多数情况下，LINQ会慢一点，因为它会引入开销。如果您非常关心...
LINQ is also calling foreach to loop, it is a extention method with IEnumerable type which records in memory.If you are doing LINQ to SQL or Entity Framework, the LINQ query will be translate to T-SQL, so the performance is good.
Console.WriteLine($"foreach loop array::{sw.ElapsedMilliseconds}ms"); sw.Restart();for(vari =0; i <100; i++) {for(varj =0; j < arr.Length; j++) { predicate(arr[j]); } } sw.Stop(); Console.WriteLine($"for loop array::{sw.ElapsedMilliseconds}ms"); 至此我们已经可以回答本文开...
在使用foreach的情况下,您可以看到实现是获取枚举数,继续使用MoveNext(),并使用currentt引用值。此外,查看list.cs *2中MoveNext()的实现,似乎增加了各种属性访问的数量,例如大小检查,并且处理比索引器直接访问更频繁。 *2 https://referencesource.microsoft.com/#mscorlib/system/collections/generic/list.cs 接下来,...
file.Length )intofileGroupwherefileGroup.Count() >1selectfileGroup;foreach(varqueryDupinqueryDupFiles.Take(20)) { Console.WriteLine($"Filename ={(queryDup.Key.ToString() ==string.Empty ?"[none]": queryDup.Key.ToString())}");foreach(varfileNameinqueryDup) { Console.WriteLine($"...
For- aforloop is used to call the indexer Foreach- aforeachloop is used to call the enumerator Has a variant: SIMD- using SIMD Usage Add theNetFabric.HyperlinqNuGet packageto your project. Optionally, also add theNetFabric.Hyperlinq.AnalyzerNuGet packageto your project. It's a Roslyn ...
When a loop is filtering, selecting or aggregating, those functions can be handled with a clearer, more concise LINQ expression instead. Noncompliant code example varresult =newList<string>();foreach(varelementincollection)// Noncompliant{if(condition(element)) ...
A query isn't executed until you iterate over the query variable, for example in aforeachstatement. At compile time, query expressions are converted to standard query operator method calls according to the rules defined in the C# specification. Any query that can be expressed by using query sy...
Console.WriteLine($"for loop array:: {sw.ElapsedMilliseconds}ms"); 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 看到了吗?使用数组下标遍历数组比使用foreach遍历集合耗时缩短了将近二分之一。
But it has the drawbacks that you cannot simply use a foreach loop, you must use a special ForAll API, and you must be careful that the lambdas do not rely on shared state. Otherwise, introducing parallelism will render your queries incorrect and can cause unpredictable crashes...