生成多边形的问题?请各位高手帮忙!

如我现在知道6个点的坐标,如何将这6个点生成一个多边形?

<P>下面的函数可以帮助你完成任务</P>
<P>Sub ConvexHull()<BR>    ' creates a polygon based on the convex hull of selected points<BR>    ' in layer(0) and adds the polygon to the current edit target layer<BR>    <BR>    Dim pMxDoc As IMxDocument<BR>    Set pMxDoc = ThisDocument<BR>    <BR>    Dim pFSel As IFeatureSelection<BR>    Set pFSel = pMxDoc.FocusMap.Layer(0)<BR>    <BR>    If pFSel.SelectionSet.Count < 3 Then<BR>        Debug.Print "not enough points selected"<BR>        Exit Sub<BR>    End If<BR>    <BR>    Dim pPolygon As IPolygon<BR>    Set pPolygon = GetConvexHull(pFSel)<BR>    If pPolygon Is Nothing Then Exit Sub<BR>    <BR>    Dim pUID As New UID<BR>    pUID.Value = "esricore.Editor"<BR>    <BR>    Dim pEditor As IEditor<BR>    Set pEditor = Application.FindExtensionByCLSID(pUID)<BR>    <BR>    If pEditor.EditState <> esriStateEditing Then<BR>        Debug.Print "not editing"<BR>        Exit Sub<BR>    End If<BR>    <BR>    Dim pEL As IEditLayers<BR>    Set pEL = pEditor<BR>    <BR>    If pEL.CurrentLayer.FeatureClass.ShapeType <> esriGeometryPolygon Then<BR>        Debug.Print "target layer is not polygon"<BR>        Exit Sub<BR>    End If<BR>    <BR>    Dim pFeat As IFeature<BR>    Set pFeat = pEL.CurrentLayer.FeatureClass.CreateFeature<BR>    <BR>    Set pFeat.Shape = pPolygon<BR>    pFeat.Store<BR>    pMxDoc.ActiveView.Refresh<BR>End Sub<BR><BR>Function GetConvexHull(pFSel As IFeatureSelection) As IPolygon<BR>    Dim pGeomColl As IGeometryCollection<BR>    Set pGeomColl = New Multipoint<BR>    <BR>    Dim pFCur As IFeatureCursor<BR>    pFSel.SelectionSet.Search Nothing, True, pFCur<BR>    Dim pFeat As IFeature<BR>    Set pFeat = pFCur.NextFeature<BR>    Do While Not pFeat Is Nothing<BR>        pGeomColl.AddGeometry pFeat.ShapeCopy<BR>        Set pFeat = pFCur.NextFeature<BR>    Loop<BR>    <BR>    Dim pTopoOp As ITopologicalOperator<BR>    Set pTopoOp = pGeomColl<BR>    Dim pGeom As IGeometry<BR>    Set pGeom = pTopoOp.ConvexHull<BR>    <BR>    If Not pGeom.GeometryType = esriGeometryPolygon Then<BR>        Debug.Print "maybe the points were colinear?"<BR>        Exit Function<BR>    End If<BR>    Set GetConvexHull = pGeom<BR>End Function<BR></P>

<img src="images/post/smile/dvbbs/em02.gif" /><img src="images/post/smile/dvbbs/em04.gif" /><img src="images/post/smile/dvbbs/em05.gif" />