请生成在arcengine中使用TIN来生成DEM。通过插值方法，将TIN的三角形内的高程值插值到栅格上，形成DEM的代码

在ArcEngine中使用TIN生成DEM并将高程值插到栅格上，可以使用以下代码示例：

// 创建TIN
ITinEdit tinEdit = new Tin();
tinEdit.InitNew(esriTinSurfaceType.esriTinHardLine);
// 将点数据添加到TIN
IPointCollection pointCollection = tinEdit as IPointCollection;
for (int i 0; i < pointFeatureClass.FeatureCount(null); i++)
{
    IFeature feature pointFeatureClass.GetFeature(i);
    IPoint point = feature.Shape as IPoint;
    tinEdit.AddPointZ(point, feature.Value[heightFieldIndex]);
}
// 构建TIN
tinEdit.UpdateTin();

// 创建栅格数据集
IRasterDataset rasterDataset = CreateRasterDataset(workspace, rasterDatasetName, extent, cellSize);

// 将TIN插值到栅格
IRasterEdit rasterEdit = rasterDataset.CreateDefaultRaster() as IRasterEdit;
IRasterSurface rasterSurface = new RasterSurfaceClass();
rasterSurface.PutTin(tinEdit);

// 设置栅格的空间参考和范围
IRasterProps rasterProps = rasterEdit as IRasterProps;
rasterProps.SpatialReference = spatialReference;
rasterProps.Extent = extent;

// 设置插值方法
IRasterAnalysisEnvironment rasterAnalysisEnvironment = rasterSurface as IRasterAnalysisEnvironment;
rasterAnalysisEnvironment.SetCellSize(esriRasterEnvSettingEnum.esriRasterEnvValue, cellSize);
rasterAnalysisEnvironment.SetExtent(esriRasterEnvSettingEnum.esriRasterEnvValue, extent);

// 执行插值过程
IRaster interpolatedRaster = rasterSurface.CreateSurface() as IRaster;

// 将插值结果写入栅格数据集
rasterEdit.Write(interpolatedRaster);

// 释放资源
Marshal.ReleaseComObject(rasterSurface);
Marshal.ReleaseComObject(tinEdit);
Marshal.ReleaseComObject(rasterEdit);
Marshal.ReleaseComObject(interpolatedRaster);

// 创建栅格数据集的方法示例
private IRasterDataset CreateRasterDataset(IWorkspace workspace, string rasterDatasetName, IEnvelope extent, double cellSize)
{
    IRasterWorkspace2 rasterWorkspace = workspace as IRasterWorkspace2;
    IRasterDataset rasterDataset = rasterWorkspace.CreateRasterDataset(rasterDatasetName, "TIFF", extent, cellSize, 1, 1);
    return rasterDataset;
}

请注意，上述代码只是一个示例，具体实现可能需要根据您的数据源、空间参考等进行调整。您需要先将点数据添加到TIN中，然后使用TIN将高程值插值到栅格上，并将结果写入栅格数据集中。最后，记得释放相关的COM对象。