MVVM and the WPF DataGrid

using System.Collections.ObjectModel;

namespace DataGridOpsDemo.ViewModel.Services
{
    public static class SequencingService
    {
        /// <summary>
        /// Resets the sequential order of a collection.
        /// </summary>
        /// <param name="targetCollection">The collection to be re-indexed.</param>
public static ObservableCollection<T> SetCollectionSequence<T>(ObservableCollection<T> targetCollection) where T : ISequencedObject
{
    // Initialize
    var sequenceNumber = 1;

    // Resequence
    foreach (ISequencedObject sequencedObject in targetCollection)
    {
        sequencedObject.SequenceNumber = sequenceNumber;
        sequenceNumber++;
    }

    // Set return value
    return targetCollection;
}
    }
}