Question

I have four string as listed below. Though they have different order of characters and different spacing after comma – they are considered to have same business value.

1. How do I check that all the strings are same (according to the business scenario explained above) ? I have following code but it fails in the case of space after comma.
2. What is the better method (for this purpose) than Enumerable.SequenceEqual?

Note: “A,B” will be considered same as “B,A,B,A,B”

Note: I am using Visual Studio 2010 with .Net Framework 4

CODE

  string firstString = "A,B,C";
  string secondString = "C,A,B";
  string thirdString = "A,B, C";
  string fourthString = "C, A,B";


  //Set 1 Test
  List<string> firstList = new List<string>(firstString.Split(','));
  List<string> secondLsit = new List<string>(secondString.Split(','));
  bool isStringsSame = Enumerable.SequenceEqual(firstList.OrderBy(t => t), secondLsit.OrderBy(t => t));
  Console.WriteLine(isStringsSame);


  //Set 2 Test
  List<string> thirdList = new List<string>(thirdString.Split(','));
  List<string> fourthList = new List<string>(fourthString.Split(','));
  bool isOtherStringsSame = Enumerable.SequenceEqual(thirdList.OrderBy(t => t), fourthList.OrderBy(t => t));
  Console.WriteLine(isOtherStringsSame);

  Console.ReadLine();

UPDATE:

Use OrdianlIgnoreCase for ignoring case sensitvity How to use HashSet<string>.Contains() method in case -insensitive mode?

REFERENCE:

1. Best way to check for string in comma-delimited list with .NET?
2. Compare two List<T> objects for equality, ignoring order
3. Why does the IEnumerable<T>.Select() works in 1 of 2 cases ? Can not be inferred from usage
4. What is the shortest code to compare two comma-separated strings for a match?
5. Split a separated string into hierarchy using c# and linq
6. Count matching characters between two strings using LINQ
7. Usinq Linq to select items that is in a semi-comma separated string?
8. Determine whether two or more objects in a list are equal according to some property

Answer 1

Would you consider A,B to be equal to B,A,B,A,B? If so, you should be using sets. If not, an ordered sequence is appropriate.

EDIT: Now we know you actually want set equality:

var set1 = new HashSet<string>(firstString.Split(',').Select(t => t.Trim()));
bool setsEqual = set1.SetEquals(secondString.Split(',').Select(t => t.Trim()));

---

If we weren’t after set equality…

To ignore the spaces, you should just trim them. For example:

var firstOrdered = firstString.Split(',')
                              .Select(t => t.Trim())
                              .OrderBy(t => t);
var secondOrdered = secondString.Split(',')
                                .Select(t => t.Trim())
                                .OrderBy(t => t); 
bool stringsAreEqual = firstOrdered.SequenceEqual(secondOrdered);