CODEWITHSUNDEEP
c#linqasp.net-mvc-4c#-4.0
cracker
cracker

Reputation: 4906

WildCard Search Using Linq

I am having a Cardtable with values

Cardtable

  ID       Card No
-------   ----------
  1     | 0001-1234-5678-9001
  2     | 0001-1234-5678-9002
  3     | 0001-1234-5678-9003
  4     | 0001-1234-5678-9004
  5     | 0001-1234-5678-9005

Now i want to search in this table using LINQ with Card No

i.e. 0001-1234-5678-9001 (Using number directly) or 0001123456789001 (Using number without dashes)

Can anyone help in this?

Upvotes: 1

Views: 717

Answers (3)

Martin Liversage
Martin Liversage

Reputation: 106826

In the comments to the other answers you have indicated that you want to execute the query on the server side. You can do this by converting the card number into a canonical card number which has the format that is used in the database:

String GetCanonicalCardNo(String cardNo) {
  if (cardNo.Length == 19)
    return cardNo;
  if (cardNo.Length != 16)
    throw new ArgumentException("Invalid card number.", "cardNo");
  return String.Format(
    "{0}-{1}-{2}-{3}",
    cardNo.Substring(0, 4),
    cardNo.Substring(4, 4),
    cardNo.Substring(8, 4),
    cardNo.Substring(12, 4)
  );
}

This function will convert the card number into 0001-1234-5678-9001.

You can then find a card using code like this:

var canonicalCardNo = GetCanonicalCardNo(cardNo);
var card = Cards.FirstOrDefault(card => card.CardNo == canonicalCardNo);

The predicate used to select the card only contains a string comparision which can be executed on the server side.

Upvotes: 4

Adil
Adil

Reputation: 148120

You can do it by comparing of condition statements in Enumerable.Where. Replacing the hypen in the CardNumber and variable will make both strings without hyphens and it will address both cases of with and without hyphen numbers. 

var result = Cardtable
            .Where(c=> c.CardNumber.Replace("-", "") == cardVariable.Replace("-", ""));

Upvotes: 2

DayDayHappy
DayDayHappy

Reputation: 1679

http://ideone.com/AyfBMm

        List<Cardtable> cardtable = new List<Cardtable>();

        cardtable.Add(new Cardtable() { id = 1, cardno = "0001-1234-5678-9001" });
        cardtable.Add(new Cardtable() { id = 2, cardno = "0001-1234-5678-9002" });

        string search_string = "0001-1234-5678-9002";
        var result = from c in cardtable
                where c.cardno.Replace("-", "") == search_string.Replace("-", "")
                select c;

        foreach (Cardtable ct in result)
        {
            Console.WriteLine("{0}:{1}", ct.id, ct.cardno);
        }

Upvotes: 1

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