怎样打开一个目录下的所有shp文件？

<P>代码如下，有问题，谁能告诉我问题出在哪里了？谢谢！</P>
<P>Dim pWorkspaceFactory As IFeatureWorkspaceFactory
Set pWorkspaceFactory = New ShapefileWorkspaceFactory
Dim pWorkSpace As IWorkspace
Set pWorkSpace = pWorkspaceFactory.OpenFromFile("E:\source\test\", 0)
 
  Dim pEnumDs As IEnumDataset
  Dim tt  As IEnumDatasetName
  </P>
<P>  Dim pEnumDstt As IFeatureDataset
  Set pEnumDs = pWorkSpace.Datasets(esriDTAny)
   Set pEnumDstt = pEnumDs .Next</P>
<P>Dim pFeatureClass As IFeatureClass
 MapControl1.Map.ClearLayers   '首先清除地图中原来的所有图层</P>
<P>  While Not pEnumDstt Is Nothing
  
   Dim pLayer As IGeoFeatureLayer
Set pLayer = New FeatureLayer</P>
<P>Set pFeatureClass = pFeatureWorkspace.OpenFeatureClass(pEnumDstt.Name)
Set pLayer.FeatureClass = pFeatureClass</P>
<P>pLayer.Name = pFeatureClass.AliasName
MapControlDisp.Map.AddLayer pLayer
Set pEnumDstt = pEnumDs.Next
 Wend</P>
<P>为什么pEnumDstt 总是nothing ?请问怎样得到文件名的集合呢？苦恼啊。。。。</P>

<P>谢谢楼上的，帮我了大忙，节约了我无数的时间，太谢谢了，我现在可以安心去吃午饭啦！</P>