C#: Sort one collection based on another

extensions_sort_collection.cs

/// <summary>
/// Sort one collection based on keys defined in another
/// </summary>
/// <returns>Items sorted</returns>
public static IEnumerable<TResult> SortBy<TResult, TKey>(
    this IEnumerable<TResult> itemsToSort,
    IEnumerable<TKey> sortKeys,
    Func<TResult, TKey> matchFunc)
{
    return sortKeys.Join(itemsToSort,
        key => key,
        matchFunc,
        (key, iitem) => iitem);
}