/// <summary>
/// 栅格计算
/// </summary>
/// <param name="mapAlgebraOp"></param>
/// <param name="expression"></param>
/// <param name="nameAndRasters"></param>
/// <returns></returns>
public static IRaster RasterCalculate(IMapAlgebraOp mapAlgebraOp, Dictionary <string, IRaster> nameAndRasters,
string expression)
{
if (mapAlgebraOp == null)
{
return(null);
}
//绑定
foreach (var item in nameAndRasters)
{
mapAlgebraOp.BindRaster((IGeoDataset)item.Value, item.Key);
}
//进行栅格计算
return((IRaster)mapAlgebraOp.Execute(expression));
}
/// <summary>
/// 执行地图代数运算
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
/// <remarks></remarks>
private void Button_OK_Click(System.Object sender, System.EventArgs e)
{
IRasterLayer pRasLayer = default(IRasterLayer);
IRaster pRaster = default(IRaster);
IEnvelope layExtend = default(IEnvelope);
double AnalysisExtentLeft = 0;
double AnalysisExtentRight = 0;
double AnalysisExtentTop = 0;
double AnalysisExtentBottom = 0;
string layerNameFir = null;
try
{
if (LayerList.Count != 0)
{
if (textBox_Result.Text.ToString().Length != 0)
{
layerNameFir = LayerList[0].ToString();
layExtend = GetLayerExtend(layerNameFir);
AnalysisExtentLeft = layExtend.XMin;
AnalysisExtentRight = layExtend.XMax;
AnalysisExtentTop = layExtend.YMax;
AnalysisExtentBottom = layExtend.YMin;
pMapAlgebraOp = new RasterMapAlgebraOp() as IMapAlgebraOp;
//设置栅格计算分析环境
IRasterAnalysisEnvironment pRasAnaEnv = default(IRasterAnalysisEnvironment);
pRasAnaEnv = (IRasterAnalysisEnvironment)pMapAlgebraOp;
pRasAnaEnv.VerifyType = esriRasterVerifyEnum.esriRasterVerifyOn;
object dddd;
dddd = GetRasterCellSize(layerNameFir);
pRasAnaEnv.SetCellSize(esriRasterEnvSettingEnum.esriRasterEnvValue, ref dddd);
//设置分析范围pAnaExtent
IEnvelope pAnaExtent = default(IEnvelope);
pAnaExtent = new Envelope() as IEnvelope;
pAnaExtent.XMin = Convert.ToDouble(AnalysisExtentLeft);
pAnaExtent.XMax = Convert.ToDouble(AnalysisExtentRight);
pAnaExtent.YMax = Convert.ToDouble(AnalysisExtentTop);
pAnaExtent.YMin = Convert.ToDouble(AnalysisExtentBottom);
object dd1 = pAnaExtent;
object dd2 = null;
pRasAnaEnv.SetExtent(esriRasterEnvSettingEnum.esriRasterEnvValue, ref dd1, ref dd2);
foreach (string LayerName in LayerList)
{
pRasLayer = (IRasterLayer)FindLayerByName(pCurMap, LayerName);
//MsgBox(LayerName)
pRaster = pRasLayer.Raster;
RasterList.Add(pRaster);
}
//将容量设置为 ArrayList 中元素的实际数目
LayerList.TrimToSize();
RasterList.TrimToSize();
//绑定
int i = 0;
if (LayerList.Count == RasterList.Count)
{
for (i = 0; i <= LayerList.Count - 1; i++)
{
pMapAlgebraOp.BindRaster((IGeoDataset)RasterList[i], LayerList[i].ToString());
}
}
//获取文本框中的运算表达式()
string sCalExpression = null;
sCalExpression = textBox_Calculate.Text;
//执行地图代数运算
IRaster pOutRasterDS = default(IRaster);
pOutRasterDS = (IRaster)pMapAlgebraOp.Execute(sCalExpression);
//解除绑定
if (LayerList.Count == RasterList.Count)
{
for (i = 0; i <= LayerList.Count - 1; i++)
{
pMapAlgebraOp.UnbindRaster(LayerList[i].ToString());
}
}
//保存到工作空间
IWorkspaceFactory pWsFact = default(IWorkspaceFactory);
IWorkspace pWS = default(IWorkspace);
int hwnd = 0;
pWsFact = new RasterWorkspaceFactory();
pWS = pWsFact.OpenFromFile(sOutRasPath, hwnd);
IRasterBandCollection pRasterbandCollection = default(IRasterBandCollection);
pRasterbandCollection = (IRasterBandCollection)pOutRasterDS;
IDataset pDataset = default(IDataset);
pDataset = pRasterbandCollection.SaveAs(sOutRasName, pWS, "IMAGINE Image");
//输出到mapcontrol中
IRasterDataset pOutResultDS = default(IRasterDataset);
pOutResultDS = (IRasterDataset)pDataset;
IRasterLayer pOutRasterLayer = default(IRasterLayer);
pOutRasterLayer = new RasterLayer();
pOutRasterLayer.CreateFromDataset(pOutResultDS);
//MapControlMain.AddLayer(pOutRasterLayer)
pCurMap.AddLayer(pOutRasterLayer);
this.Close();
}
else
{
MessageBox.Show("保存计算结果为空，请输入结果文件名！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Error, MessageBoxDefaultButton.Button1);
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
//Interaction.MsgBox(ex.ToString);
}
}
private void btnOK_Click(object sender, EventArgs e)
{
try
{
pMapAlgebraOp= new RasterMapAlgebraOpClass();
string strExpression = "";
string dP = "",dCN="";
dP = "[" + this.cmbPcp.Text + "]";
dCN = "[" + this.cmbCN.Text + "]";
ILayer pLayer = null;
IRaster pRater = null;
IGeoDataset pGeoDataset = null;
pLayer = this.pMap.get_Layer(LayerOprate.getLayerIndexByName(pMap,this.cmbPcp.Text));
pRater=(pLayer as IRasterLayer).Raster;
pGeoDataset = pRater as IGeoDataset;
pMapAlgebraOp.BindRaster(pGeoDataset, pLayer.Name);
pLayer = this.pMap.get_Layer(LayerOprate.getLayerIndexByName(pMap, this.cmbCN.Text));
pRater = (pLayer as IRasterLayer).Raster;
pGeoDataset = pRater as IGeoDataset;
pMapAlgebraOp.BindRaster(pGeoDataset, pLayer.Name);
pLayer = null;
pRater = null;
pGeoDataset = null;
// S=25400/CN-254
// Q=(P-0.2S)^2/(P+0.8S) P>0.2S
// Q=0 P>0.2S
//Con(P>0.2S,(P-0.2S)^2/(P+0.8S),0)
//Con(P>0.2*(25400/CN-254),(P-0.2*(25400/CN-254))^2/(P+0.8*(25400/CN-254)),0)
strExpression = "25400.0 / ("+dCN+" * 1.0) - 254";
IGeoDataset pGeoDsS = pMapAlgebraOp.Execute(strExpression);
pMapAlgebraOp.BindRaster(pGeoDsS, "S");
string dS="[S]";
string saveFileName = this.txtSavePath.Text.Trim();
if (saveFileName == "")
{
strExpression = "Con(" + dP + " > 0.2 * " + dS + ",(" + dP + " - 0.2 * " + dS + ") * (" + dP + " - 0.2 * " + dS + ") / (" + dP + " + 0.8 * " + dS + "),0)";
}
else
{
strExpression =saveFileName+" = " +strExpression;
}
IGeoDataset pGeoDsQ = pMapAlgebraOp.Execute(strExpression);
IRaster pOutRaster = pGeoDsQ as IRaster;
IRasterLayer pOutRasterLayer = new RasterLayerClass();
//pOutRasterLayer = SetStretchRenderer(pOutRaster);
pOutRasterLayer.CreateFromRaster(pOutRaster);
pMap.AddLayer(pOutRasterLayer);
pGeoDsQ = null;
pGeoDsS = null;
pMapAlgebraOp = null;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message.ToString());
}
}