怎么输出集合中的元素值？

Private Sub Command1_Click()
Dim a As New Collection
a.Add "nihao", "123"
a.Add "nihao1", "1233"
a.Add "nihao2", "12333"
a.Add "nihao3", "12343"
a.Add "nihao4", "12323"
Dim b
For Each b In a
Text1.Text = a.Item("nihao1")//wrong!!!!!!!!!!!!!
Next b
End Sub