CODEWITHSUNDEEP
c#genericscollectionstype-conversion
jamiei
jamiei

Reputation: 2036

Most succinct way to convert ListBox.items to a generic list

I am using C# and targeting the .NET Framework 3.5. I'm looking for a small, succinct and efficient piece of code to copy all of the items in a ListBox to a List<String> (Generic List).

At the moment I have something similar to the below code: 

        List<String> myOtherList =  new List<String>();
        // Populate our colCriteria with the selected columns.

        foreach (String strCol in lbMyListBox.Items)
        {
            myOtherList.Add(strCol);
        }

Which works, of course, but I can't help but get the feeling that there must be a better way of doing this with some of the newer language features. I was thinking of something like the List.ConvertAll method but this only applies to Generic Lists and not ListBox.ObjectCollection collections.

Upvotes: 64

Views: 72833

Answers (5)

iruisoto
iruisoto

Reputation: 21

You don't need more. You get List of all values from Listbox

private static List<string> GetAllElements(ListBox chkList)
        {
            return chkList.Items.Cast<ListItem>().Select(x => x.Value).ToList<string>();
        }

Upvotes: 2

Konamiman
Konamiman

Reputation: 50273

What about:

myOtherList.AddRange(lbMyListBox.Items);

EDIT based on comments and DavidGouge's answer:

myOtherList.AddRange(lbMyListBox.Items.Select(item => ((ListItem)item).Value));

Upvotes: 2

AnthonyWJones
AnthonyWJones

Reputation: 189437

A bit of LINQ should do it:-

 var myOtherList = lbMyListBox.Items.Cast<String>().ToList();

Of course you can modify the Type parameter of the Cast to whatever type you have stored in the Items property.

Upvotes: 122

adrianbanks
adrianbanks

Reputation: 82934

The following will do it (using Linq):

List<string> list = lbMyListBox.Items.OfType<string>().ToList();

The OfType call will ensure that only items in the listbox's items that are strings are used.

Using Cast, if any of the the items are not strings, you will get an exception.

Upvotes: 31

DavidGouge
DavidGouge

Reputation: 4623

How about this:

List<string> myOtherList = (from l in lbMyListBox.Items.Cast<ListItem>() select l.Value).ToList();

Upvotes: 5

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