/// <summary>
/// 复制旧要素图层（只包含选中字段）
/// </summary>
/// <param name="featureWorkspace">要素工作空间</param>
/// <param name="selectionLayer">被复制要素图层</param>
/// <param name="newLayerName">新图层名称</param>
/// <returns></returns>
private IFeatureLayer CopyOldFeatureLayerWithSelectFiled(IFeatureWorkspace featureWorkspace,
IFeatureLayer selectionLayer, string newLayerName)
{
Dictionary <string, int> fidValue = DataTableInfoClass.GetColumnValueDictionary(newAttributeTable, "FID"); //FID值列表
List <string> columnName = DataTableInfoClass.GetAllColumnName(newAttributeTable); //表格所有列名
IWorkspaceEdit workspaceEdit = featureWorkspace as IWorkspaceEdit;
if (workspaceEdit == null)
{
return(null);
}
//开始编辑
StartEdit(workspaceEdit);
try
{
//以旧图层为基础创建新图层要素集合
IFeatureClass newFeatureClass = CreateNewFeatureClass(featureWorkspace, selectionLayer, newLayerName);
//复制旧要素值到新要素集合
CopyFeatureValueToNewFeature(selectionLayer, newFeatureClass, fidValue, columnName);
//停止并保存编辑
EndAndSaveEdit(workspaceEdit);
//删除非选中字段
DeleteFeatureClassFields(newFeatureClass, columnName);
return(FeatureInfoClass.GetFeatureLayer(newFeatureClass));
}
finally
{
//撤销编辑
UndoEdit(workspaceEdit);
}
}
/// <summary>
/// 计算要素FID和面积
/// </summary>
/// <param name="vectorFile"></param>
/// <returns></returns>
public static Dictionary <string, double> ComputeFeatureFidAndArea(string vectorFile)
{
IFeatureLayer featureLayer = FeatureInfoClass.GetFeatureLayer(vectorFile);
IQueryFilter pFilter = new QueryFilterClass();
pFilter.SubFields = "Shape, FID"; //设置过滤字段，提高效率
IFeatureCursor featureCursor = featureLayer.Search(pFilter, false);
return(ComputeAreaByCursor(featureCursor));
}
/// <summary>
/// 复制图层
/// </summary>
/// <param name="inFile">输入文件</param>
/// <param name="outFile">输出文件</param>
/// <returns></returns>
private static IFeatureLayer CopyLayer(string inFile, string outFile)
{
IFeatureClass featureClass = FeatureInfoClass.GetFeatureClass(inFile);
IDataset dataset = featureClass as IDataset;
if (dataset == null || !dataset.CanCopy())
{
return(null);
}
DatasetHelper.CopyDatasetAsFeatureLayer(dataset, outFile);
return(FeatureInfoClass.GetFeatureLayer(outFile));
}
/// <summary>
/// 创建新图层
/// </summary>
/// <param name="saveFile">保存路径</param>
/// <returns></returns>
private IFeatureLayer CreateNewLayer(string saveFile)
{
string saveName = Path.GetFileNameWithoutExtension(saveFile);
IFeatureLayerDefinition featureLayerDefinition = oldFeatureLayer as IFeatureLayerDefinition;
if (featureLayerDefinition == null)
{
return(null);
}
//从要素图层的选择集中创建新要素图层
IFeatureLayer selectionLayer = featureLayerDefinition.CreateSelectionLayer(saveName, true, null, null);
//打开要素工作空间
IFeatureWorkspace pFeatureWorkspace = (IFeatureWorkspace)FeatureInfoClass.GetShapefileWorkspace(saveFile);
if (pFeatureWorkspace == null || selectionLayer == null)
{
return(null);
}
IFeatureLayer copyFeatureLayer = CopyOldFeatureLayerWithSelectFiled(pFeatureWorkspace, selectionLayer, saveName);
return(copyFeatureLayer);
}
/// <summary>
/// 创建新的字段
/// </summary>
/// <param name="vectorFile"></param>
/// <param name="newFieldTable"></param>
public NewFieldCreateClass(string vectorFile, DataTable newFieldTable)
{
newFieldLayer = FeatureInfoClass.GetFeatureLayer(vectorFile);
this.newFieldTable = newFieldTable;
}
private readonly IFeatureLayer oldFeatureLayer; //被查询的旧图层
/// <summary>
/// 创建新的要素图层
/// </summary>
/// <param name="inVectorFile"></param>
/// <param name="newLayerTable"></param>
public NewFeatureLayerCreateClass(string inVectorFile, DataTable newLayerTable)
{
oldFeatureLayer = FeatureInfoClass.GetFeatureLayer(inVectorFile);
newAttributeTable = newLayerTable;
}
