Copy list of of objects to another list of another objects within another object

Question

My method returns a response object which contains a list of objects.

public class GetAccountsListResponse
{
    public List<AccountsList> Accounts { get; set; }
}

public class AccountsList
{
    public string AccountId { get; set; }
    public string AccountName { get; set; }

}

I tried something like this, but im getting null refernce exception :

public GetAccountsListResponse GetAccountsList()
    {

        AccountRepository objRepo = new AccountRepository();
        GetAccountsListResponse res = new GetAccountsListResponse();

        List<Account> lstAccnts = new List<Account>();
        lstAccnts = objRepo.GetAccountsFromRepo();

        foreach (var item in lstAccnts)
        {
            res.Accounts = new List<AccountsList>();
            res.Accounts.ForEach(c => c.AccountId = item.AccountId);    

        }

        return res;
    }

Please help me to fix the issue.

Looks like lstAccnts *might* be coming back null from the call `objRepo.GetAccountsFromRepo()`. — Baldrick, Mar 05 '14 at 09:46
`res.Accounts = new List(); res.Accounts.ForEach(c => c.AccountId = item.AccountId);` These two lines doesn't makes sense. you create `new List<>` and `ForEach` ? It will always have zero elements — Sriram Sakthivel, Mar 05 '14 at 09:47
@K.B im getting error in res.Accounts.ForEach(c => c.AccountId = item.AccountId); — Imp, Mar 05 '14 at 09:52
@Sriram Sakthivel can u pls help me fix the issue, if u have understood the question? — Imp, Mar 05 '14 at 09:54
Check my answer [here](http://stackoverflow.com/questions/22146277/how-to-know-an-exact-location-of-nullreferenceexception/22146474#22146474) to track where the null reference exception happens. Then you can fix it by checking for null or instantiating new object. — Sriram Sakthivel, Mar 05 '14 at 09:57
You start the confusion by naming an AccountItem an AccountList. And then there is your are creating (empty) lists everywhere. — H H, Mar 05 '14 at 09:59

BRAHIM Kamel · Accepted Answer · 2014-03-05T10:04:57.633

3

that's obvious as you are only creating a new list with no object instantiated at all try something like this

    res.Accounts = new List<AccountsList>();
    foreach (var item in lstAccnts)
    {

        res.Accounts.Add( new AccountsList(){AccountId =item.AccountId});    

    }

edited Mar 05 '14 at 10:04

answered Mar 05 '14 at 09:59

BRAHIM Kamel

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This also doesn't makes sense – Sriram Sakthivel Mar 05 '14 at 10:00
answer edited take a look now why not this will create a new list from the lstAccnts and add items to res.Accounts – BRAHIM Kamel Mar 05 '14 at 10:05

Copy list of of objects to another list of another objects within another object

1 Answers1