Anyone please clear my doubt on reference Types?

Question

Consider the Below Code, int [] intArray = new int [] { 10, 20, 20, 12, 15, 22, 11, 45, 15, 45 }; intArray.Distinct(); foreach ( int num in intArray) { Console.Write(num + " " ); } Array is a Reference type. But when I use Distinct on Array it is not affected. I am confused here. Please anyone clear it.

Jaish Mathews · Answer

The way you chosen is not correct as Distinct() is a utility function and it has a return value too. i.e. if value returns, you need to store it in a variable and use it. The underlying object won't modify here. See below string example too. You know string is Ref. .NET string name = "Jaish Mathews"; name.Replace("J","M"); You will not get the replace value inside variable "name", but need to store it in another variable. So takeaway is that if any utility method returns, you need to store it and then use it. Now how to prove array is Ref., type? Use data assignment technique. See below code. int[] intArray = new int[] { 10, 20, 20, 12, 15, 22, 11, 45, 15, 45 }; int[] intArray1 = intArray; intArray1[1] = 100; I copied your array to another variable and then modify this latest variable. Then see this modification has been reflected to your original one too. So don't confuse with utility methods. For checking Ref. and Val. types, always use data assignment techniques like this.

Bohdan Stupak · Answer

It's because Distinct is a pure function which doesn't modify input but returns result instead. This should help int [] intArray = new int [] { 10, 20, 20, 12, 15, 22, 11, 45, 15, 45 }; var res = intArray.Distinct(); foreach ( int num in res) { Console.Write(num + " " ); }

Anyone please clear my doubt on reference Types?

Answers (2)