C# finding item in List<>

Question

I have a list which contains a collection of objects.

How can I search for an item in this list where object.Property == myValue

Answer 1

item = objects.Find(obj => obj.property==myValue);

Answer 2

You have a few options:

1. Using Enumerable.Where:

   list.Where(i => i.Property == value).FirstOrDefault();       // C# 3.0+
   

2. Using List.Find:

   list.Find(i => i.Property == value);                         // C# 3.0+
   list.Find(delegate(Item i) { return i.Property == value; }); // C# 2.0+
   

Both of these options return default(T) (null for reference types) if no match is found.

As mentioned in the comments below, you should use the appropriate form of comparison for your scenario:

• == for simple value types or where use of operator overloads are desired
• object.Equals(a,b) for most scenarios where the type is unknown or comparison has potentially been overridden
• string.Equals(a,b,StringComparison) for comparing strings
• object.ReferenceEquals(a,b) for identity comparisons, which are usually the fastest

Answer 3

What is wrong with List.Find ??

I think we need more information on what you've done, and why it fails, before we can provide truly helpful answers.

Answer 4

var myItem = myList.Find(item => item.property == "something");

Answer 5

For .NET 2.0:

list.Find(delegate(Item i) { return i.Property == someValue; });