Is IEnumerable faster than List C#?
IEnumerable is conceptually faster than List because of the deferred execution. Deferred execution makes IEnumerable faster because it only gets the data when needed. Contrary to Lists having the data in-memory all the time.
Why we use IEnumerable instead of List?
IEnumerable is best to query data from in-memory collections like List, Array etc. IEnumerable doesn’t support add or remove items from the list. Using IEnumerable we can find out the no of elements in the collection after iterating the collection. IEnumerable supports deferred execution.
Should I pass IEnumerable or List?
Passing collections into methods
If your method needs to accept a collection as a parameter, then generally IEnumerable<T> is the best choice. This offers the most flexibility to the caller. It doesn’t matter what concrete collection type they use, and it even allows them to pass lazily evaluated sequences in.
Is List an IEnumerable C#?
IEnumerable is read-only and List is not. IEnumerable types have a method to get the next item in the collection. It doesn’t need the whole collection to be in memory and doesn’t know how many items are in it, foreach just keeps getting the next item until it runs out.
Which collection is faster in C#?
ListDictionary is faster than Hashtable for small collections (10 items or fewer). The Dictionary<TKey,TValue> generic class provides faster lookup than the SortedDictionary<TKey,TValue> generic class.
Should I repository return List or IEnumerable?
It depends on whether you wish to have any future queries performed on the entity and whether these should be in memory or not: If there are to be future queries and the DB should do the work return IQueryable. If there are to be future queries and it is to be done in memory return IEnumerable.
Is IQueryable faster than list?
GetList(context) might return an object backed by a custom LINQ provider (like an Entity Framework collection), then you probably want to leave the data cast as an IQueryable: even though your benchmark shows it being 20 times faster to use a list, that difference is so small that no user is ever going to be able to …
Should I repository return list or IEnumerable?
Should I use IList or ICollection?
IList<T> is essentially an ICollection<T> with random order-based access. In this case you should decide whether or not your results require list semantics such as order based indexing (then use IList<T> ) or whether you just need to return an unordered “bag” of results (then use ICollection<T> ).
Is IQueryable faster than List?
Is array faster than list C#?
In general, one would opt for using Lists (List) due to their flexibility in size. On top of that, msdn documentation claims Lists use an array internally and should perform just as fast (a quick look with Reflector confirms this).
How can I make my C# code run faster?
Here are 5 easy ways to make your C# application run faster.
- Use XmlNodeReader over XPath. The XmlNodeReader and XmlTextReader will perform significantly faster than using any XPath expression.
- Use String. Compare instead of =’s.
- Avoid many calls to Guid.NewGuid()
- Use For instead of ForEach.
- Use Release Mode.
What is difference between List and IList in C#?
The main difference between List and IList in C# is that List is a class that represents a list of objects which can be accessed by index while IList is an interface that represents a collection of objects which can be accessed by index.
What repository pattern should return?
Your repositories should return domain objects and the client of the repository can decide if it needs to do the mapping. By mapping the domain objects to view models (or something else) inside a repository, you prevent the client of your repositories from getting access to the underlying domain object.
Which is faster IQueryable or IEnumerable?
IQueryable is faster than IEnumerable. In addition to Munesh Sharma’s answer:IEnumerable loads data in-memory and then apply filters to it one by one but IQueryable apply filters all at once and return the result.
Which is better IQueryable or IEnumerable?
So if you working with only in-memory data collection IEnumerable is a good choice but if you want to query data collection which is connected with database `IQueryable is a better choice as it reduces network traffic and uses the power of SQL language.
What is difference between IList and IEnumerable?
IList doesn’t support further filtering. IEnumerable exists in System. Collections Namespace. IEnumerable is a forward only collection, it can’t move backward and between the items.
What is difference between IEnumerable and ICollection?
An ICollection is an IEnumerable with easy access to things like Add , Remove , and Count . An IEnumerable is anything that can be enumerated, even if the list of those things doesn’t exist until you enumerate it.
Which is the fastest collection in C#?
A HashSet, similar to a Dictionary, is a hash-based collection, so look ups are very fast with O(1). But unlike a dictionary, it doesn’t store key/value pairs; it only stores values.
Why Dict is faster than list?
The reason is because a dictionary is a lookup, while a list is an iteration. Dictionary uses a hash lookup, while your list requires walking through the list until it finds the result from beginning to the result each time.
Why C# is faster than Java?
C# is generally considered faster than Java, although the difference is insignificant. Both languages are compiled, but C# uses a just-in-time compiler while Java uses an ahead-of-time compiler. This means that C# code is typically executed more quickly.
Why is Visual Studio so heavy?
This is mainly because Visual Studio has lots of components, extensions and tools.
Which is better IList or list?
Can a repository return DTO?
Short answer: No. Long answer: repository is responsible for turning persisted data back to entities (models) and vice versa. Model is a business Model representing a business entity.
What is the difference between Dao and repository?
DAO is an abstraction of data persistence. However, a repository is an abstraction of a collection of objects. DAO is a lower-level concept, closer to the storage systems. However, Repository is a higher-level concept, closer to the Domain objects.