Best way to update an element in a generic List [duplicate]

Question

Suppose we have a class called Dog with two strings "Name" and "Id". Now suppose we have a list with 4 dogs in it. If you wanted to change the name of the Dog with the "Id" of "2" what would be the best way to do it?

Dog d1 = new Dog("Fluffy", "1"); Dog d2 = new Dog("Rex", "2"); Dog d3 = new Dog("Luna", "3"); Dog d4 = new Dog("Willie", "4");  List<Dog> AllDogs = new List<Dog>() AllDogs.Add(d1); AllDogs.Add(d2); AllDogs.Add(d3); AllDogs.Add(d4); 

Answer 1

AllDogs.First(d => d.Id == "2").Name = "some value"; 

However, a safer version of that might be this:

var dog = AllDogs.FirstOrDefault(d => d.Id == "2"); if (dog != null) { dog.Name = "some value"; } 

Answer 2

You could do:

var matchingDog = AllDogs.FirstOrDefault(dog => dog.Id == "2")); 

This will return the matching dog, else it will return null.

You can then set the property like follows:

if (matchingDog != null)     matchingDog.Name = "New Dog Name";