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byte_coder23
·
IEnumerable and List in C#: what to choose and how do they work?
Hi! I'm a beginner in C# and often get confused when I need to choose between IEnumerable and List. For example, I write a method that returns a list of numbers from a database:
```csharp
public List GetNumbers()
{
var numbers = new List();
for (int i = 0; i < 10; i++)
{
numbers.Add(i);
}
return numbers;
}
```
But my colleague said it's better to return IEnumerable. I don't understand why. Also I noticed that in LINQ methods like Where() return IEnumerable, and ToList() converts it to a List. When I write:
```csharp
var query = numbers.Where(n => n > 5);
foreach (var n in query)
{
Console.WriteLine(n);
}
```
Everything works, but I don't know what's happening "under the hood". Is there a difference in performance? Can I modify elements in I
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