IRasterLayer pDEMRLayer = axMapControl1.get_Layer(1) as IRasterLayer;
IRaster pDEMR = pDEMRLayer.Raster;
IRasterProps pRasterProps = (IRasterProps)(pDEMRLayer.Raster);
//儲存每個柵格的X座標和Y座標
double blockX = pRasterProps.MeanCellSize().X;
double blockY = pRasterProps.MeanCellSize().Y;
//柵格資料左上角柵格的空間座標
double Xm = pRasterProps.Extent.XMin + blockX / 2;
double Ym = pRasterProps.Extent.YMin + blockX / 2;
int dHeight = pRasterProps.Height;//當前柵格資料集的行數
int dWidth = pRasterProps.Width; //當前柵格資料集的列數
IPnt pnt = new PntClass();
 //讀取柵格資訊
pnt.SetCoords(0, 0);//0，0取值視窗的起始位置在原柵格資料上的位置
IPnt pntSize = new PntClass();
pntSize.SetCoords(dWidth, dHeight);//設定取值視窗的行列，注意這裡是先列後行
IPixelBlock pixelBlock = pDEMR.CreatePixelBlock(pntSize);//生成畫素塊
pDEMR.Read(pnt, pixelBlock);
List<IPoint> depthList = new List<IPoint>(); 
for (int i = 0; i < dHeight; i++)
     for (int j = 0; j < dWidth; j++)
     {
         object obj = Convert.ToDouble(pixelBlock.GetVal(0, i, j));
     }