ITopologicalOperator接口调用

 ITopologicalOperator 接口：

1. Provides additional information on non-simple geometries.【拓扑操作】

　　Members

		Description
	Boundary 返回值：IGeometry	这个几何体的边界。多边形的边界是多段线。多段线的边界是多点。点或多点的边界是空点或多点。
	Buffer (double distance) 返回值：IGeometry	构造一个多边形，该多边形是距离此几何体小于或等于指定距离的点的轨迹。 通过给定距离，得到操作图形的缓冲区，返回得到缓冲区几何图形！
	Clip (IEnvelope clipperEnvelope)	Constructs the intersection of this geometry and the specified envelope. 返回矩形部分的要素，直接作用在要素上面！
	ClipDense	Constructs the intersection of this geometry and the specified envelope; densifies lines in output contributed by the clipping envelope.
	ClipEx	Constructs the intersection of this geometry and the specified envelope.
	ClipToDomain	Clips the geometry to the domain of the spatial reference. Useful for ensuring that buffers can be fit within the spatial domain of the feature class to which they are being added.
	ConstructUnion	Defines this geometry to be the union of the inputs. More efficient for unioning multiple geometries than calling Union repeatedly.
	ConvexHull	Constructs the convex hull of this geometry.
	Cut	Splits this geometry into a part left of the cutting polyline, and a part right of it.
	Cut2	Divides a geometry into multiple parts
	Difference	Constructs the geometry containing points from this geometry but not the other geometry.
	GeoNormalizeEx	Shifts longitudes, if need be, into a continuous range of 360 degrees.
	Intersect	Constructs the geometry that is the set-theoretic intersection of the input geometries. Use different resultDimension values to generate results of different dimensions.
	IntersectMultidimension	Constructs the set-theoretic intersection of the inputs. The results are returned in a geometry bag with one element per result dimension.
	IsKnownSimple	Indicates whether this geometry is known (or assumed) to be topologically correct.
	IsKnownSimple	Indicates whether this geometry is known (or assumed) to be topologically correct.
	IsSimple	Indicates whether this geometry is known (or assumed) to be topologically correct, after explicitly determining this if the geometry is not already known (or assumed) to be simple.
	IsSimpleEx	Determines why a geometry is not simple. Currently only implemented for polygons.
	QueryClipped	Redefines clippedGeometry to be the intersection of this geometry and the clipping envelope.
	QueryClippedDense	Redefines clippedGeometry to be the intersection of this geometry and the clipping envelope; densifies lines in the output contributed by the clipping envelope.
	Simplify	Makes this geometry topologically correct.
	SymmetricDifference	Constructs the geometry that contains points from either but not both input geometries.
	Union	Constructs the geometry that is the set-theoretic union of the input geometries.

　　CoClasses that implement ITopologicalOperator

CoClasses and Classes	Description
GeoEllipse (esriDefenseSolutions)	Its a spheroidal ellipse.
GeometryBag	An ordered collection of objects that support the IGeometry interface.
GeoPolygon (esriDefenseSolutions)	Its a spheroidal polygon.
GeoPolyline (esriDefenseSolutions)	This is a spheroidal polyline.
MultiPatch	A collection of surface patches.
Multipoint	An ordered collection of points; optionally has measure, height and ID attributes.
Point	A two dimensional point, optionally with measure, height, and ID attributes.
Polygon	A collection of rings ordered by their containment relationship; optionally has measure, height and ID attributes.
Polyline	An ordered collection of paths; optionally has measure, height and ID attributes.

※ | ※ → 公共代码部分：

//公共变量！~

IMap pMap;
IActiveView pActiveView;
IEnvelope pEnv;
ISelectionEnvironment pSelectionEnv;
IEnumFeature pEnumFeature;
IGraphicsContainer pGraphicsContainer;
IFeature pFeature;
IGeometry pGeometry;
IEnvelope pEnvClip;
IPolyline pLineCut;
IPolygon pFirstPolygon;

//鼠标点击事件！~

private void axMapControl1_OnMouseDown(object sender, IMapControlEvents2_OnMouseDownEvent e)
{
    axMapControl1.MousePointer = esriControlsMousePointer.esriPointerCrosshair;
    if (isClip) //此时要拉Clip框
    {
        pEnvClip = axMapControl1.TrackRectangle();
        isClip = false;
    }
    else if (isCut)
    {
        pLineCut = axMapControl1.TrackLine() as IPolyline;
        isCut = false;
    }
    else if (isFirstIn)
    {
        pMap = axMapControl1.Map;
        pActiveView = pMap as IActiveView;
        pEnv = axMapControl1.TrackRectangle();

        pSelectionEnv = new SelectionEnvironment();
        pSelectionEnv.DefaultColor = GetColor(0, 255, 0);
        pMap.SelectByShape(pEnv, pSelectionEnv, false);
        pActiveView.Refresh();
        pEnumFeature = axMapControl1.Map.FeatureSelection as IEnumFeature;
    }
    else
    {
        pMap = axMapControl1.Map;
        pActiveView = pMap as IActiveView;
        pEnv = axMapControl1.TrackRectangle();

        pSelectionEnv = new SelectionEnvironment();
        pSelectionEnv.DefaultColor = GetColor(255, 0, 0);
        pMap.SelectByShape(pEnv, pSelectionEnv, false);
        pActiveView.Refresh();
        pEnumFeature = axMapControl1.Map.FeatureSelection as IEnumFeature;
    }
}

//RGB颜色！~

private IRgbColor GetColor(int r, int g, int b)
{
    IRgbColor pColor = new RgbColor();
    pColor.Red = r;
    pColor.Green = g;
    pColor.Blue = b;
    return pColor;
}

※ | ※ → Buffer：

private void button1_Click(object sender, EventArgs e)
{
    while (true)
    {
        pGraphicsContainer = pMap as IGraphicsContainer;    //定义容器
        pFeature = pEnumFeature.Next();     //遍历要素
        if (pFeature == null)            //若不存在要素，则推出循环
            break;
        pGeometry = pFeature.Shape;     //获取要素的Geometry
        ITopologicalOperator pTopoOperator = pGeometry as ITopologicalOperator; //QI到拓扑操作
        IGeometry pBufferGeo = pTopoOperator.Buffer(2);     //缓冲区分析

        IElement pElement = new PolygonElement();
        pElement.Geometry = pBufferGeo;     //获取得到的缓冲区

        pGraphicsContainer.AddElement(pElement, 0); //显示缓冲区
        pActiveView.Refresh();
    }
}

※ | ※ → Boundary：

private void button2_Click(object sender, EventArgs e)
{
    while (true)
    {
        pGraphicsContainer = pMap as IGraphicsContainer;    //定义容器
        pFeature = pEnumFeature.Next();     //遍历要素
        if (pFeature == null)            //若不存在要素，则推出循环
            break;
        pGeometry = pFeature.Shape;     //获取要素的Geometry
        ITopologicalOperator pTopoOperator = pGeometry as ITopologicalOperator; //QI到拓扑操作
        IGeometry pBoundary = pTopoOperator.Boundary;  //获取边界

        ILineElement pLineEle = new LineElementClass();
        ISimpleLineSymbol pSLS = new SimpleLineSymbol();
        IRgbColor pColor = GetColor(0, 255, 0);
        pSLS.Color = pColor;
        pSLS.Width = 5;
        pLineEle.Symbol = pSLS;

        IElement pElement = pLineEle as IElement;
        pElement.Geometry = pBoundary;

        pGraphicsContainer.AddElement(pElement, 0); //显示边界
        pActiveView.Refresh();
    }
}

※ | ※ → Clip：

bool isClip = false;
private void button3_Click(object sender, EventArgs e)
{
    isClip = true;
}

private void button4_Click(object sender, EventArgs e)
{
    while (true)
    {
        pGraphicsContainer = pMap as IGraphicsContainer;    //定义容器
        pFeature = pEnumFeature.Next();     //遍历要素
        if (pFeature == null)            //若不存在要素，则推出循环
            break;
        pGeometry = pFeature.Shape;     //获取要素的Geometry
        ITopologicalOperator pTopoOperator = pGeometry as ITopologicalOperator; //QI到拓扑操作
        pTopoOperator.Clip(pEnvClip);

        IElement pElement = new PolygonElement();
        pElement.Geometry = pGeometry;     //获取得到的缓冲区

        pGraphicsContainer.AddElement(pElement, 0); //显示缓冲区
        pActiveView.Refresh();
    }
}

※ | ※ → ConvexHull：

private void button5_Click(object sender, EventArgs e)
{
    while (true)
    {
        pGraphicsContainer = pMap as IGraphicsContainer;    //定义容器
        pFeature = pEnumFeature.Next();     //遍历要素
        if (pFeature == null)            //若不存在要素，则推出循环
            break;
        pGeometry = pFeature.Shape;     //获取要素的Geometry
        ITopologicalOperator pTopoOperator = pGeometry as ITopologicalOperator; //QI到拓扑操作
        IGeometry pBufferGeo = pTopoOperator.ConvexHull();

        IElement pElement = new PolygonElement();
        pElement.Geometry = pBufferGeo;     //获取得到的缓冲区

        pGraphicsContainer.AddElement(pElement, 0); //显示缓冲区
        pActiveView.Refresh();
    }
}

※ | ※ → Cut：

bool isCut = false;

private void button6_Click(object sender, EventArgs e)
{
    isCut = true;
}

private void button7_Click(object sender, EventArgs e)
{
    while (true)
    {
        pGraphicsContainer = pMap as IGraphicsContainer;    //定义容器
        pFeature = pEnumFeature.Next();     //遍历要素
        if (pFeature == null)            //若不存在要素，则推出循环
            break;
        pGeometry = pFeature.Shape;     //获取要素的Geometry
        ITopologicalOperator pTopoOperator = pGeometry as ITopologicalOperator; //QI到拓扑操作ry
        IGeometry pGeoRight = new PolygonClass();
        IGeometry pGeoLeft = new PolygonClass();
        pTopoOperator.Cut(pLineCut, out pGeoLeft, out pGeoRight);

        IElement pElement = new PolygonElement();

        IFillShapeElement pFillEle = pElement as IFillShapeElement;
        ISimpleFillSymbol pSFS = new SimpleFillSymbol();
        pSFS.Color = GetColor(255, 255, 0);
        pFillEle.Symbol = pSFS;

        pElement.Geometry = pGeoLeft;     //获取得到的缓冲区
        pGraphicsContainer.AddElement(pElement, 0); //显示缓冲区

        pSFS = new SimpleFillSymbol();
        pSFS.Color = GetColor(255, 0, 255);
        pFillEle.Symbol = pSFS;

        pElement = new PolygonElement();
        pElement.Geometry = pGeoRight;     //获取得到的缓冲区
        pGraphicsContainer.AddElement(pElement, 0); //显示缓冲区

        pActiveView.Refresh();
    }
}

※ | ※ → Union：

private void button8_Click(object sender, EventArgs e)
{
    IGeometry pUnionGeo = new PolygonClass();
    pGraphicsContainer = pMap as IGraphicsContainer;    //定义容器

    while (true)
    {
        pFeature = pEnumFeature.Next();     //遍历要素
        if (pFeature == null)            //若不存在要素，则推出循环
            break;
        pGeometry = pFeature.Shape;     //获取要素的Geometry
        ITopologicalOperator pTopoOperator = pUnionGeo as ITopologicalOperator; //QI到拓扑操作ry
        pUnionGeo = pTopoOperator.Union(pGeometry);
    }

    IElement pElement = new PolygonElement();

    IFillShapeElement pFillEle = pElement as IFillShapeElement;
    ISimpleFillSymbol pSFS = new SimpleFillSymbol();
    pSFS.Color = GetColor(255, 255, 0);
    pFillEle.Symbol = pSFS;

    pElement.Geometry = pUnionGeo;     //获取得到的缓冲区
    pGraphicsContainer.AddElement(pElement, 0); //显示缓冲区

    pActiveView.Refresh();
}

※ | ※ → Intersect：

bool isFirstIn = false;

private void button10_Click(object sender, EventArgs e)
{
    isFirstIn = true;
}

private void button11_Click(object sender, EventArgs e)
{
    isFirstIn = false;
    pFirstPolygon = new PolygonClass();
    while (true)
    {
        pFeature = pEnumFeature.Next();
        if (pFeature == null)
            break;
        pGeometry = pFeature.Shape;
        ITopologicalOperator pTopoOperator = pFirstPolygon as ITopologicalOperator;
        pFirstPolygon = pTopoOperator.Union(pGeometry) as IPolygon;
    }
}

private void button12_Click(object sender, EventArgs e)
{
    IGeometry pIntersectGeo = new PolygonClass();
    IGeometry pSecondPolygon = new PolygonClass();
    pGraphicsContainer = pMap as IGraphicsContainer;

    while (true)
    {
        pFeature = pEnumFeature.Next();
        if (pFeature == null)
            break;
        pGeometry = pFeature.Shape;
        ITopologicalOperator pTopoOperator = pSecondPolygon as ITopologicalOperator;
        pSecondPolygon = pTopoOperator.Union(pGeometry) as IPolygon;
    }

    ITopologicalOperator pTopo = pSecondPolygon as ITopologicalOperator;
    pIntersectGeo = pTopo.Intersect(pFirstPolygon, esriGeometryDimension.esriGeometry2Dimension) as  IPolygon;
    IElement pElement = new PolygonElementClass();
    pElement.Geometry = pIntersectGeo;
    pGraphicsContainer.AddElement(pElement, 0);
    IFeatureLayer pFeatureLayer = pMap.get_Layer(0) as IFeatureLayer;
    pFeatureLayer.Visible = false;
    pFeatureLayer = pMap.get_Layer(1) as IFeatureLayer;
    pFeatureLayer.Visible = false;
    pActiveView.Refresh();
}

※ | ※ → Difference：（需要前面两部分）

private void button13_Click(object sender, EventArgs e)
{
    IGeometry pIntersectGeo = new PolygonClass();
    IGeometry pSecondPolygon = new PolygonClass();
    pGraphicsContainer = pMap as IGraphicsContainer;

    while (true)
    {
        pFeature = pEnumFeature.Next();
        if (pFeature == null)
            break;
        pGeometry = pFeature.Shape;
        ITopologicalOperator pTopoOperator = pSecondPolygon as ITopologicalOperator;
        pSecondPolygon = pTopoOperator.Union(pGeometry) as IPolygon;
    }

    ITopologicalOperator pTopo = pSecondPolygon as ITopologicalOperator;
    pIntersectGeo = pTopo.Difference(pFirstPolygon) as IPolygon;
    IElement pElement = new PolygonElementClass();
    pElement.Geometry = pIntersectGeo;
    pGraphicsContainer.AddElement(pElement, 0);
    IFeatureLayer pFeatureLayer = pMap.get_Layer(0) as IFeatureLayer;
    pFeatureLayer.Visible = false;
    pFeatureLayer = pMap.get_Layer(1) as IFeatureLayer;
    pFeatureLayer.Visible = false;
    pActiveView.Refresh();
}

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╠════╣    第A2个    ╠══════════════════════════════════════════════════╣
            ╚════════╝

●·● IRelationalOperator 接口：

1. Provides access to members that determine if a certain spatial relationship exists between two geometries.

　　Members

		Description
	Contains	Indicates if this geometry contains the other geometry. 前者是否包含后者！
	Crosses	Indicates if the two geometries intersect in a geometry of lesser dimension.
	Disjoint	Indicates if the two geometries share no points in common. Negate this result to compute the Intersect relation.
	Equals	Indicates if the two geometries are of the same type and define the same set of points in the plane.
	Overlaps	Indicates if the intersection of the two geometries has the same dimension as one of the input geometries. 前者和后者是否有重叠！不包括包含关系！
	Relation	Indicates if the defined relationship exists.
	Touches	Indicates if the boundaries of the geometries intersect.
	Within	Indicates if this geometry is contained (is within) another geometry. 前者是否在后者内部！

　　CoClasses that implement IRelationalOperator

CoClasses and Classes	Description
Envelope	A rectangle with sides parallel to a coordinate system defining the extent of another geometry; optionally has min and max measure, height and ID attributes.
GeometryBag	An ordered collection of objects that support the IGeometry interface.
MultiPatch	A collection of surface patches.
Multipoint	An ordered collection of points; optionally has measure, height and ID attributes.
Point	A two dimensional point, optionally with measure, height, and ID attributes.
Polygon	A collection of rings ordered by their containment relationship; optionally has measure, height and ID attributes.
Polyline	An ordered collection of paths; optionally has measure, height and ID attributes.

※ | ※ → 公共代码部分：

IMap pMap;
IActiveView pActiveView;
IEnvelope pEnv;
ISelectionEnvironment pSelectionEnv;
IEnumFeature pEnumFeature;
IFeature pFeature;
IGeometry pGeometry;
IGeometry pBasicGeo;

private void axMapControl1_OnMouseDown(object sender, IMapControlEvents2_OnMouseDownEvent e)
{
    axMapControl1.MousePointer = esriControlsMousePointer.esriPointerCrosshair;
    pMap = axMapControl1.Map;
    pActiveView = pMap as IActiveView;
    pEnv = axMapControl1.TrackRectangle();
    pSelectionEnv = new SelectionEnvironment();
    pSelectionEnv.DefaultColor = GetColor(255, 0, 0);
    pMap.SelectByShape(pEnv, pSelectionEnv, false);
    pActiveView.Refresh();
    pEnumFeature = pMap.FeatureSelection as IEnumFeature;
}

private IRgbColor GetColor(int r, int g, int b)
{
    IRgbColor pColor = new RgbColor();
    pColor.Red = r;
    pColor.Green = g;
    pColor.Blue = b;
    return pColor;
}

private IGeometry GetBasicGeometry()
{
    IFeatureLayer pFeatureLayer = axMapControl1.Map.get_Layer(1) as IFeatureLayer;
    IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;
    IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, false);
    IFeature pF = pFeatureCursor.NextFeature();
    IGeometry pUnionGeo = new PolygonClass();
    pUnionGeo = pF.Shape;
    while(pF != null)
    {
        ITopologicalOperator pUnionTopo = pUnionGeo as ITopologicalOperator;
        pUnionGeo = pUnionTopo.Union(pF.Shape);
        pF = pFeatureCursor.NextFeature();
    }
    return pUnionGeo;
}

private void Form1_Load(object sender, EventArgs e)
{
    (axMapControl1.get_Layer(1) as IFeatureLayer).Selectable = false;
}

※ | ※ → Contains：

private void button5_Click(object sender, EventArgs e)
{
    pBasicGeo = GetBasicGeometry();
    pGeometry = new PolygonClass();
    while (true)
    {
        pFeature = pEnumFeature.Next();
        if (pFeature == null)
            break;
        ITopologicalOperator pTopo = pGeometry as ITopologicalOperator;
        pGeometry = pTopo.Union(pFeature.Shape);
    }

    IRelationalOperator pRO = pBasicGeo as IRelationalOperator;
    bool IsContains = pRO.Contains(pGeometry);
    if (IsContains)
    {
        MessageBox.Show("Basic图层数据 包含 选中数据！");
    }
    else
    {
        MessageBox.Show("Basic图层数据 不包含 选中数据！");
    }
}

※ | ※ → Overlaps：

private void button2_Click(object sender, EventArgs e)
{
    pBasicGeo = GetBasicGeometry();
    pGeometry = new PolygonClass();
    while (true)
    {
        pFeature = pEnumFeature.Next();
        if (pFeature == null)
            break;
        ITopologicalOperator pTopo = pGeometry as ITopologicalOperator;
        pGeometry = pTopo.Union(pFeature.Shape);
    }

    IRelationalOperator pRO = pGeometry as IRelationalOperator;
    bool IsContains = pRO.Overlaps(pBasicGeo);
    if (IsContains)
    {
        MessageBox.Show("选中数据 重叠 Basic图层数据！");
    }
    else
    {
        MessageBox.Show("选中数据 不重叠 Basic图层数据！");
    }
}
转自https://www.cnblogs.com/alex-bn-lee/archive/2012/06/17/2552557.html