How to convert IEnumerable to ObservableCollection?

Question

How to convert IEnumerable to ObservableCollection?

score 220 · Answer 1 · edited Apr 10 '15 at 12:42

220

As per the MSDN

var myObservableCollection = new ObservableCollection<YourType>(myIEnumerable);

This will make a shallow copy of the current IEnumerable and turn it in to a ObservableCollection.

edited Apr 10 '15 at 12:42

Silverstein

96
6

answered Aug 24 '10 at 18:39

Scott Chamberlain

116,967
28
260
389

Is this quicker than using a ForEach loop to insert the items one by one into the collection? – Rexxo Aug 31 '16 at 12:49
4

@Rexxo it will be slightly faster to do it with the constructor. Internally [it is using a `foreach`](http://referencesource.microsoft.com/System/compmod/system/collections/objectmodel/observablecollection.cs.html#cfaa9abd8b214ecb) to copy the items to the internal collection, however if you do the foreach and call `Add` [it will be going through `InsertItem`](http://referencesource.microsoft.com/System/compmod/system/collections/objectmodel/observablecollection.cs.html#767bf62bf4a3a7c1) which does a lot of extra stuff that is unessesary when initially filling causing it to be slightly slower. – Scott Chamberlain Aug 31 '16 at 13:05
Simples and the best answer – peterincumbria Sep 30 '18 at 12:51

score 76 · Answer 2 · edited Dec 25 '15 at 13:58

If you're working with non-generic IEnumerable you can do it this way:

public ObservableCollection<object> Convert(IEnumerable original)
{
    return new ObservableCollection<object>(original.Cast<object>());
}

If you're working with generic IEnumerable<T> you can do it this way:

public ObservableCollection<T> Convert<T>(IEnumerable<T> original)
{
    return new ObservableCollection<T>(original);
}

If you're working with non-generic IEnumerable but know the type of elements, you can do it this way:

public ObservableCollection<T> Convert<T>(IEnumerable original)
{
    return new ObservableCollection<T>(original.Cast<T>());
}

score 33 · Answer 3 · edited May 23 '17 at 12:02

33

To make things even more simple you can create an Extension method out of it.

public static class Extensions
{
    public static ObservableCollection<T> ToObservableCollection<T>(this IEnumerable<T> col)
    {
        return new ObservableCollection<T>(col);
    }
}

Then you can call the method on every IEnumerable

var lst = new List<object>().ToObservableCollection();

edited May 23 '17 at 12:02

Community

1
1

answered Nov 06 '12 at 19:01

markwilde

1,702
1
14
23

1

Cool answer for a cool question, I add this to pinned answers. – Raiden Core Apr 25 '21 at 01:15

score 3 · Answer 4 · edited May 29 '15 at 07:42

3

ObservableCollection<decimal> distinctPkgIdList = new ObservableCollection<decimal>();
guPackgIds.Distinct().ToList().ForEach(i => distinctPkgIdList.Add(i));

// distinctPkgIdList - ObservableCollection
// guPackgIds.Distinct() - IEnumerable

edited May 29 '15 at 07:42

joergl

2,842
4
34
42

answered Jun 16 '14 at 06:11

Sudharshan

320
1
9

score 1 · Answer 5 · answered Nov 16 '15 at 12:37

The C# Function to Convert the IEnumerable to ObservableCollection

private ObservableCollection<dynamic> IEnumeratorToObservableCollection(IEnumerable source)
    {

        ObservableCollection<dynamic> SourceCollection = new ObservableCollection<dynamic>();

        IEnumerator enumItem = source.GetEnumerator();
        var gType = source.GetType();
        string collectionFullName = gType.FullName;
        Type[] genericTypes = gType.GetGenericArguments();
        string className = genericTypes[0].Name;
        string classFullName = genericTypes[0].FullName;
        string assName = (classFullName.Split('.'))[0];

        // Get the type contained in the name string
        Type type = Type.GetType(classFullName, true);

        // create an instance of that type
        object instance = Activator.CreateInstance(type);
        List<PropertyInfo> oProperty = instance.GetType().GetProperties().ToList();
        while (enumItem.MoveNext())
        {

            Object instanceInner = Activator.CreateInstance(type);
            var x = enumItem.Current;

            foreach (var item in oProperty)
            {
                if (x.GetType().GetProperty(item.Name) != null)
                {
                    var propertyValue = x.GetType().GetProperty(item.Name).GetValue(x, null);
                    if (propertyValue != null)
                    {
                        PropertyInfo prop = type.GetProperty(item.Name);
                        prop.SetValue(instanceInner, propertyValue, null);
                    }
                }
            }

            SourceCollection.Add(instanceInner);
        }

        return SourceCollection;
    }

How to convert IEnumerable to ObservableCollection?

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