Using Linq to replace foreach statement

Question

I'm a little bit confused by the explanations of linq online so I figured I'd make a thread.

I want to replace my foreach statements with linq statements as I'm sure doing little things like this will make me program better.

Example of what I'd like to use LINQ with:

 public bool CheckForAccount(int accountID)
        {
            bool status = false;

            foreach (AccountHolders accountHolder in AccountHoldersList)
            {
                if (accountHolder.AccountNumber == accountID)
                {
                    status = true;
                    break;
                }
            }
            return status;
        }

Please can you provide an explanation of how it works too so I understand what you're doing.

Thanks in advance!

score 6 · Accepted Answer · answered Apr 14 '14 at 16:26

6

So probably the most succinct statement would be:

public bool CheckForAccount(int accountId)
{
    return this.AccountHolderList.Any(x => x.AccountNumber == accountId);
}

In English this says

Check AccountHolderList for any cases where the AccountNumber property is equal to accountId. If there are any, return true, otherwise return false.

answered Apr 14 '14 at 16:26

dav_i

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you are one second faster :) +1 – Selman Genç Apr 14 '14 at 16:27
Can you please explain what you're code is saying? thanks in advance – Zain Apr 14 '14 at 16:28
@user3245390 Updated to include description of code. Though it should be obvious from the code :) – dav_i Apr 14 '14 at 16:32
well mine will also work now..:P but lots of downvotes got..:( – Ehsan Sajjad Apr 14 '14 at 16:56
i was not aware of any() method and its working, today learned new thing from your answer..@dav_i – Ehsan Sajjad Apr 14 '14 at 16:57
I've upvoted it @EhsanSajjad , thanks for trying to help me! + thank you everyone. Answer marked as answered now :) – Zain Apr 15 '14 at 08:39

score 0 · Answer 2 · edited May 23 '17 at 10:28

0

both

AccountHolderList.Any(x => x.AccountNumber == accountId);

and

AccountHoldersList.Exists(p => p.AccountNumber == accountId);

work equally well. Here is a more in-depth explanation of the differences: Linq .Any VS .Exists - Whats the difference?

You could also use this:

  var match = AccountHolderList.FirstOrDefault(x => x.AccountNumber == accountId);
  return match != null ? true : false;

if you want to get a reference to the match as well. This works assuming accountId is unique

edited May 23 '17 at 10:28

Community

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answered Apr 14 '14 at 17:09

Mr Balanikas

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`return match != null ? true : false;` can be replaced just by `return match != null;`. It currently reads "if match not equal to null returns true return true otherwise return false" – dav_i Apr 15 '14 at 09:47

Using Linq to replace foreach statement

2 Answers2