Büyülenme Hakkında C# IEnumerable Kullanımı

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If an airline is "countable", this means that there MUST be a flight attendant present on the plane, whose sole job is to count:

What this code is saying is that if userId was specified, then add a filter on the data so that only items where the userId matches that variable will be included. That same thing is done for email and lastFourdigits.

This where filter is executed on the client side where the IEnumerable code is. In other words all the veri is fetched from the database and then at the client its scans and gets the record with EmpId is 2.

But now see the below code we have changed IEnumerable to IQueryable. It creates a SQL Query at the server side and only necessary veri is sent to the client side.

An Enumerable is a class that hayat give you Enumerators. It katışıksız a method called GetEnumerator which gives you an Enumerator that looks at its items. When you write a foreach loop in C#, the code that it generates calls GetEnumerator to create the Enumerator used by the loop.

So if you working with only in-memory data collection IEnumerable is a good choice but if you want to query veri collection which is connected with database `IQueryable is a better choice birli it reduces network C# IEnumerable Nedir traffic and uses the power of SQL language.

This is a birçok video on youtube which demonstrates how these interfaces differ , worth a watch. Below goes a long descriptive answer for it.

What US checks and balances prevent the FBI from raiding politicians unfavorable to the federal government?

but this violates the IEnumerable semantics and the time came when I got wrong results. so switched to orderly creating a fresh iterator instance (see my answer)

There are pros and cons to both. If you call ToList, you may remove some mystery kakım to when the query gets executed. If you stick to IEnumerable, you get the advantage that the program doesn't do any work until it's actually required.

And that C# IEnumerable Nasıl Kullanılır might be useful and more efficient in certain cases. For example, your class might derece hold any collection in memory, but rather iterate over all files existing in a certain directory, or items in certain DB, or other unmanaged resources. IEnumerable gönül step in and do it C# IEnumerable Temel Özellikleri for you (you could also do it without IEnumerable, but IEnumerable "fits" conceptually, plus it gives you the benefit of being able to use the object produced C# IEnumerable Nerelerde Kullanılıyor in a foreach loop).

The reason, of course, is that someone dirilik call the first method passing in an array object, a List object, a String object, and C# IEnumerable Kullanımı so on — any object whose type implements IEnumerable.

user541686user541686 208k132132 gold badges547547 silver badges911911 bronze badges 3 i also used this and was loooong happy.

By "functionally equivalent," I mean that's actually what the compiler turns the code into. You dirilik't use foreach on temel in this example unless