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debug_master90
·
When to use .First() and when .FirstOrDefault() in LINQ in C#?
Hello everyone! I recently started learning C# and LINQ, and I encountered a confusing situation. There are two similar methods: `.First()` and `.FirstOrDefault()`. I understand that both return the first element of a sequence, but what is the difference between them?
Let's say I have a list of users:
```csharp
List users = new List { "Alice", "Bob", "Charlie" };
```
If I write:
```csharp
string firstUser = users.First(u => u.StartsWith("Z"));
```
then I get an `InvalidOperationException`. But if I use `.FirstOrDefault()`:
```csharp
string firstUser = users.FirstOrDefault(u => u.StartsWith("Z"));
```
then there is no exception, and `firstUser` equals `null`.
But when is which option more correct to use? I read that `.First()` throws an exception if nothing
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