Public Sub AddRange( _
   ByVal items As IEnumerable(Of KeyValuePair(Of TKey,TValue)) _
) 

public void AddRange( 
   IEnumerable<KeyValuePair<TKey,TValue>> items
)

BTreeDictionary<int, string> data = new BTreeDictionary<int, string>(Comparer, GetSample());
BTreeDictionary<int, string> copy = new BTreeDictionary<int, string>();
copy.AddRange(data);
Assert.AreEqual(copy.Count, data.Count);
foreach (int key in data.Keys)
    Assert.AreEqual(data[key], copy[key]);

Dim data As New BTreeDictionary(Of Integer, String)(Comparer, GetSample())
Dim copy As New BTreeDictionary(Of Integer, String)()
copy.AddRange(data)
Assert.AreEqual(copy.Count, data.Count)
For Each key As Integer In data.Keys
    Assert.AreEqual(data(key), copy(key))
Next