对矢量数据进行欧式距离计算

欧式距离计算，采用SpatialAnalystTools中的EucDistance ，比较方便，其中GetFeatureClassEnvelop，GetPathFromFeatureClass，GetRasterDatasetFromSourceData，GetRasterFromRasterDataset是另外写的函数（这几个函数写的很搞笑，就是些RasterDataset、Raster和FeatureClass、shp之间的关系及转换，其实可以不用这么写的，高手要是见了，估计会狂鄙视我的，呵呵）。

Public Function Eucdistance(ByVal SourceFeatureClass As IFeatureClass, ByVal ExtentFeatureClass As IFeatureClass, ByVal MaxDistance As Integer, ByVal EuclideanRaster_SavePath As String, ByVal EuclideanRaster_SaveName As String, ByVal CellSize As Integer) As IRaster

        '得到矢量数据的范围
        Dim pEnv As IEnvelope
        pEnv = RasterHelper.GetFeatureClassEnvelop(ExtentFeatureClass)

        '通过FeatureClass得到矢量数据的路径
        Dim SourceDataPathName As String
        SourceDataPathName = GetPathFromFeatureClass(SourceFeatureClass)

        '设置欧式距离计算器的参数
        Dim Eucdist As EucDistance = New EucDistance()
        With Eucdist
            .cell_size = CellSize
            .maximum_distance = MaxDistance
            .in_source_data = SourceDataPathName
            .out_distance_raster = EuclideanRaster_SavePath & EuclideanRaster_SaveName & ".img"
        End With

        '设置运算的环境变量
        Dim str As String = pEnv.XMin & " " & pEnv.YMax & " " & pEnv.XMax & " " & pEnv.YMin

        Dim GeoPro As New ESRI.ArcGIS.Geoprocessor.Geoprocessor
        GeoPro.SetEnvironmentValue("extent", str)

        '进行欧式距离计算，得到结果
        Dim result As IGeoProcessorResult
        result = GeoPro.Execute(Eucdist, Nothing)

        '得到结果数据的路径
        Dim RasterFullpath As String
        RasterFullpath = Eucdist.out_distance_raster

        '通过结果数据路径得到RasterDataset
        Dim pRasterDataset As IRasterDataset
        pRasterDataset = GetRasterDatasetFromSourceData(RasterFullpath)

        '通过RasterDataset得到Raster
        Dim pRaster As IRaster
        pRaster = GetRasterFromRasterDataset(pRasterDataset)

        Return pRaster

    End Function