用程序实现从带高程的点数据到等高线的转换

内容摘要 从高程点到等高线不是一步实现的，而是先把高程点先插值生成TIN，然后再从TIN生成等高线。在从TIN到等高线的生成过程中8.3和9.0上还有点区别，请看代码注释。下面的是整个过程的代码实例。 过程描述 '打开高程点数据<BR>Dim pFeatureLayer As IFeatureLayer<BR>Set pFeatureLayer = MapControl1.Map.Layer(0)<BR>If pFeatureLayer Is Nothing Then Exit Sub<BR>Dim pFeatureClass As IFeatureClass<BR>Set pFeatureClass = pFeatureLayer.FeatureClass<BR><BR>'生成TIN<BR>Dim pTinEdit As ITinEdit<BR>Dim pTinSurface As ISurface<BR>Dim pTable As ITable<BR>Set pTinEdit = New Tin<BR>Set pTable = New FeatureLayer<BR>pTinEdit.InitNew MapControl1.ActiveView.Extent<BR>Dim pField As IField<BR>Set pField = pFeatureClass.Fields.Field(pFeatureClass.Fields.FindField("Well_Dpth"))<BR>pTinEdit.AddFromFeatureClass pFeatureClass, Nothing, pField, Nothing, 18<BR><BR>Set pTinSurface = pTinEdit<BR><BR>'打开已经创建好的空的等高线数据(也可以在此时创建一个要素类9，如果是9.0版本的话，在空等高线数据中预先需要建一个字段来存储高<BR>'程值，如果是8.3版本的话就不可以预先创建这样的一个高程字段，而是在生成等高线过程中根据你指定的<BR>'字段名称实时创建<BR>Dim pPropset As IPropertySet<BR>Set pPropset = New PropertySet<BR><BR>Dim pFact As IWorkspaceFactory<BR>Dim pWorkspace As IWorkspace<BR><BR>pPropset.SetProperty "DATABASE", App.Path + "\data\"<BR><BR>Set pFact = New ShapefileWorkspaceFactory<BR>Set pWorkspace = pFact.Open(pPropset, Me.hWnd)<BR><BR>Dim pFeatureWorkspace As IFeatureWorkspace<BR>Set pFeatureWorkspace = pWorkspace<BR><BR>Dim pFeatureClass1 As IFeatureClass<BR>Set pFeatureClass1 = pFeatureWorkspace.OpenFeatureClass("MyShape33")<BR><BR>'生成等高线<BR>pTinSurface.Contour 0, 50, pFeatureClass1, "Well_Dpth", 1<BR><BR>Dim pFLayer As IFeatureLayer<BR>Set pFLayer = New FeatureLayer<BR>Set pFLayer.FeatureClass = pFeatureClass1<BR><BR>MapControl1.AddLayer pFLayer<BR>MapControl1.ActiveView.Refresh

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