1、前言

在ArcEngine中，图层标注用的还是很多的，下面就来介绍一下ArcEngine中的标注功能。首先准备一份面要素文件，其属性表如下图所示：

2、图层标注

2.1、基本标注
基本标注可以利用ITextSymbol接口实现，代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.DataSourcesFile;
using ESRI.ArcGIS.DataSourcesGDB;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Output;
using ESRI.ArcGIS.SystemUI;
using stdole;

namespace WinApp
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
            axMapControl1.LoadMxFile(@"C:\Users\DSF\Desktop\data\无标题.mxd");
            axMapControl1.Extent = axMapControl1.FullExtent;
        }

        // 标注
        private void btnLabel_Click(object sender, EventArgs e)
        {
            // 创建颜色
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 255;
            pRgbColor.Green = 0;
            pRgbColor.Blue = 0;

            // 创建字体
            IFontDisp pFontDisp = new StdFont() as IFontDisp;
            pFontDisp.Bold = true;
            pFontDisp.Name = "楷体";
            pFontDisp.Size = 20;
            
            // 创建符号
            ITextSymbol pTextSymbol = new TextSymbol();
            pTextSymbol.Angle = 0;
            pTextSymbol.Color = pRgbColor;
            pTextSymbol.Font = pFontDisp;
            
            // 删除已有文本元素
            IActiveView pActiveView = axMapControl1.ActiveView;
            IGraphicsContainer pGraphicsContainer = pActiveView.GraphicsContainer;
            pGraphicsContainer.DeleteAllElements();

            // 获取要素游标
            IFeatureLayer pFeatureLayer = axMapControl1.get_Layer(0) as IFeatureLayer;
            IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;
            IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, true);
            IFeature pFeature = pFeatureCursor.NextFeature();

            // 遍历要素游标
            int fieldIndex = pFeatureClass.Fields.FindField("Name");
            while (pFeature != null)
            {
                // 获取重心
                IArea pArea = pFeature.ShapeCopy as IArea;
                IPoint pPoint = pArea.Centroid;

                // 创建文本元素
                ITextElement pTextElement = new TextElement() as ITextElement;
                pTextElement.Symbol = pTextSymbol;
                pTextElement.Text = pFeature.get_Value(fieldIndex).ToString();

                // 添加文本元素
                IElement pElement = pTextElement as IElement;
                pElement.Geometry = pPoint;
                pGraphicsContainer.AddElement(pElement, 0);
                pFeature = pFeatureCursor.NextFeature();
            }

            // 刷新地图
            System.Runtime.InteropServices.Marshal.ReleaseComObject(pFeatureCursor);
            pActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null);
        }
    }
}

除了ITextSymbol接口，也可以利用标注引擎实现，代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.DataSourcesFile;
using ESRI.ArcGIS.DataSourcesGDB;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Output;
using ESRI.ArcGIS.SystemUI;
using stdole;

namespace WinApp
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
            axMapControl1.LoadMxFile(@"C:\Users\DSF\Desktop\data\无标题.mxd");
            axMapControl1.Extent = axMapControl1.FullExtent;
        }

        // 标注
        private void btnLabel_Click(object sender, EventArgs e)
        {
            // 创建颜色
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 255;
            pRgbColor.Green = 0;
            pRgbColor.Blue = 0;

            // 创建字体
            IFontDisp pFontDisp = new StdFont() as IFontDisp;
            pFontDisp.Bold = true;
            pFontDisp.Name = "楷体";
            pFontDisp.Size = 20;
            
            // 创建符号
            ITextSymbol pTextSymbol = new TextSymbol();
            pTextSymbol.Angle = 0;
            pTextSymbol.Color = pRgbColor;
            pTextSymbol.Font = pFontDisp;

            // 开启图层标注
            IGeoFeatureLayer pGeoFeatureLayer = axMapControl1.get_Layer(0) as IGeoFeatureLayer;
            pGeoFeatureLayer.DisplayAnnotation = true;
            IBasicOverposterLayerProperties pBasicOverposterLayerProprties = new BasicOverposterLayerProperties();
            pBasicOverposterLayerProprties.FeatureType = esriBasicOverposterFeatureType.esriOverposterPolygon;

            // 设置标注属性
            ILabelEngineLayerProperties pLabelEngineLayerProperties = new LabelEngineLayerProperties() as ILabelEngineLayerProperties;
            pLabelEngineLayerProperties.Expression = "[" + "Name" + "]";
            pLabelEngineLayerProperties.Symbol = pTextSymbol;
            pLabelEngineLayerProperties.BasicOverposterLayerProperties = pBasicOverposterLayerProprties;

            // 刷新地图
            IAnnotateLayerProperties pAnnotateLayerProperties = pLabelEngineLayerProperties as IAnnotateLayerProperties;
            IAnnotateLayerPropertiesCollection pAnnotateLayerPropertiesCollection = pGeoFeatureLayer.AnnotationProperties;
            pAnnotateLayerPropertiesCollection.Clear();
            pAnnotateLayerPropertiesCollection.Add(pAnnotateLayerProperties);
            axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewBackground, null, null);
        }
    }
}

运行结果如下图所示：

2.2、设置显示标注的比例尺
有时候我们只需要在比例尺为1:8000到1:12000时显示标注，其余比例尺下不显示标注，你可以这么做：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.DataSourcesFile;
using ESRI.ArcGIS.DataSourcesGDB;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Output;
using ESRI.ArcGIS.SystemUI;
using stdole;

namespace WinApp
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
            axMapControl1.LoadMxFile(@"C:\Users\DSF\Desktop\data\无标题.mxd");
            axMapControl1.Extent = axMapControl1.FullExtent;
        }

        // 标注
        private void btnLabel_Click(object sender, EventArgs e)
        {
            // 创建颜色
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 255;
            pRgbColor.Green = 0;
            pRgbColor.Blue = 0;

            // 创建字体
            IFontDisp pFontDisp = new StdFont() as IFontDisp;
            pFontDisp.Bold = true;
            pFontDisp.Name = "楷体";
            pFontDisp.Size = 20;

            // 创建符号
            ITextSymbol pTextSymbol = new TextSymbol();
            pTextSymbol.Angle = 0;
            pTextSymbol.Color = pRgbColor;
            pTextSymbol.Font = pFontDisp;

            // 标注位置
            ILineLabelPosition pLineLabelPosition = new LineLabelPosition();
            pLineLabelPosition.Parallel = true;
            pLineLabelPosition.Perpendicular = true;
            pLineLabelPosition.InLine = true;

            // 标注冲突
            ILineLabelPlacementPriorities pLineLabelPlacementPriorities = new LineLabelPlacementPriorities();
            pLineLabelPlacementPriorities.AboveStart = 5;
            pLineLabelPlacementPriorities.BelowAfter = 4;

            // 开启标注
            IGeoFeatureLayer pGeoFeatureLayer = axMapControl1.get_Layer(0) as IGeoFeatureLayer;
            pGeoFeatureLayer.DisplayAnnotation = true;
            IBasicOverposterLayerProperties pBasicOverposterLayerProperties = new BasicOverposterLayerProperties();
            pBasicOverposterLayerProperties.FeatureType = esriBasicOverposterFeatureType.esriOverposterPolygon;
            pBasicOverposterLayerProperties.LineLabelPlacementPriorities = pLineLabelPlacementPriorities;
            pBasicOverposterLayerProperties.LineLabelPosition = pLineLabelPosition;

            // 创建标注对象
            ILabelEngineLayerProperties pLabelEngineLayerProperties = new LabelEngineLayerProperties() as ILabelEngineLayerProperties;
            pLabelEngineLayerProperties.Symbol = pTextSymbol;
            pLabelEngineLayerProperties.BasicOverposterLayerProperties = pBasicOverposterLayerProperties;
            pLabelEngineLayerProperties.IsExpressionSimple = true;
            pLabelEngineLayerProperties.Expression = "[Name]";

            // 设置标注的参考比例尺
            IAnnotateLayerTransformationProperties pAnnotateLayerTransformationProperties = pLabelEngineLayerProperties as IAnnotateLayerTransformationProperties;
            pAnnotateLayerTransformationProperties.ReferenceScale = 2500000;

            // 设置标注的最大最小比例尺
            IAnnotateLayerProperties pAnnotateLayerProperties = pLabelEngineLayerProperties as IAnnotateLayerProperties;
            pAnnotateLayerProperties.AnnotationMaximumScale = 8000;
            pAnnotateLayerProperties.AnnotationMinimumScale = 12000;

            // 刷新地图
            IAnnotateLayerPropertiesCollection pAnnotateLayerPropertiesCollection = pGeoFeatureLayer.AnnotationProperties;
            pAnnotateLayerPropertiesCollection.Clear();
            pAnnotateLayerPropertiesCollection.Add(pAnnotateLayerProperties);
            axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewBackground, null, null);
        }
    }
}

2.3、水平分子式标注
在ArcMap中，我们可以利用VBScript或JScript或Python实现这一功能，ArcEngine的实现代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.DataSourcesFile;
using ESRI.ArcGIS.DataSourcesGDB;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Output;
using ESRI.ArcGIS.SystemUI;
using stdole;

namespace WinApp
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
            axMapControl1.LoadMxFile(@"C:\Users\DSF\Desktop\data\无标题.mxd");
            axMapControl1.Extent = axMapControl1.FullExtent;
        }

        // 标注
        private void btnLabel_Click(object sender, EventArgs e)
        {
            // 创建颜色
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 255;
            pRgbColor.Green = 0;
            pRgbColor.Blue = 0;

            // 创建字体
            IFontDisp pFontDisp = new StdFont() as IFontDisp;
            pFontDisp.Bold = true;
            pFontDisp.Name = "楷体";
            pFontDisp.Size = 20;

            // 创建符号
            ITextSymbol pTextSymbol = new TextSymbol();
            pTextSymbol.Angle = 0;
            pTextSymbol.Color = pRgbColor;
            pTextSymbol.Font = pFontDisp;

            // 标注位置
            ILineLabelPosition pLineLabelPosition = new LineLabelPosition();
            pLineLabelPosition.Parallel = true;
            pLineLabelPosition.Perpendicular = true;
            pLineLabelPosition.InLine = true;

            // 标注冲突
            ILineLabelPlacementPriorities pLineLabelPlacementPriorities = new LineLabelPlacementPriorities();
            pLineLabelPlacementPriorities.AboveStart = 5;
            pLineLabelPlacementPriorities.BelowAfter = 4;

            // 开启标注
            IGeoFeatureLayer pGeoFeatureLayer = axMapControl1.get_Layer(0) as IGeoFeatureLayer;
            pGeoFeatureLayer.DisplayAnnotation = true;
            IBasicOverposterLayerProperties pBasicOverposterLayerProperties = new BasicOverposterLayerProperties();
            pBasicOverposterLayerProperties.FeatureType = esriBasicOverposterFeatureType.esriOverposterPolygon;
            pBasicOverposterLayerProperties.LineLabelPlacementPriorities = pLineLabelPlacementPriorities;
            pBasicOverposterLayerProperties.LineLabelPosition = pLineLabelPosition;

            // 创建标注对象
            ILabelEngineLayerProperties pLabelEngineLayerProperties = new LabelEngineLayerProperties() as ILabelEngineLayerProperties;
            pLabelEngineLayerProperties.Symbol = pTextSymbol;
            pLabelEngineLayerProperties.BasicOverposterLayerProperties = pBasicOverposterLayerProperties;
            pLabelEngineLayerProperties.IsExpressionSimple = true;
            pLabelEngineLayerProperties.Expression = "\"姓名:\" & [Name] &vbnewline&\"-----------------\" &vbnewline &\"编号:\"& [Code]";

            // 设置标注的参考比例尺
            IAnnotateLayerTransformationProperties pAnnotateLayerTransformationProperties = pLabelEngineLayerProperties as IAnnotateLayerTransformationProperties;
            pAnnotateLayerTransformationProperties.ReferenceScale = 2500000;

            // 设置标注的最大最小比例尺
            IAnnotateLayerProperties pAnnotateLayerProperties = pLabelEngineLayerProperties as IAnnotateLayerProperties;
            pAnnotateLayerProperties.AnnotationMaximumScale = 8000;
            pAnnotateLayerProperties.AnnotationMinimumScale = 12000;

            // 刷新地图
            IAnnotateLayerPropertiesCollection pAnnotateLayerPropertiesCollection = pGeoFeatureLayer.AnnotationProperties;
            pAnnotateLayerPropertiesCollection.Clear();
            pAnnotateLayerPropertiesCollection.Add(pAnnotateLayerProperties);
            axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewBackground, null, null);
        }
    }
}

运行结果如下图所示：
2.4、气泡标注
气泡标注的实现代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.DataSourcesFile;
using ESRI.ArcGIS.DataSourcesGDB;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Output;
using ESRI.ArcGIS.SystemUI;
using stdole;

namespace WinApp
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
            axMapControl1.LoadMxFile(@"C:\Users\DSF\Desktop\data\无标题.mxd");
            axMapControl1.Extent = axMapControl1.FullExtent;
        }

        // 标注
        private void btnLabel_Click(object sender, EventArgs e)
        {
            // 创建颜色
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 255;
            pRgbColor.Green = 0;
            pRgbColor.Blue = 0;

            // 创建字体
            IFontDisp pFontDisp = new StdFont() as IFontDisp;
            pFontDisp.Bold = true;
            pFontDisp.Name = "楷体";
            pFontDisp.Size = 20;

            // 删除已有文本元素
            IActiveView pActiveView = axMapControl1.ActiveView;
            IGraphicsContainer pGraphicsContainer = pActiveView.GraphicsContainer;
            pGraphicsContainer.DeleteAllElements();

            // 获取要素游标
            IFeatureLayer pFeatureLayer = axMapControl1.get_Layer(0) as IFeatureLayer;
            IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;
            IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, true);
            IFeature pFeature = pFeatureCursor.NextFeature();

            // 遍历要素游标
            int fieldIndex = pFeatureClass.Fields.FindField("Name");
            while (pFeature != null)
            {
                // 获取重心
                IArea pArea = pFeature.ShapeCopy as IArea;
                IPoint pLabelPoint = pArea.LabelPoint;

                // 文本符号
                ITextSymbol pTextSymbol = new TextSymbol();
                pTextSymbol.Angle = 0;
                pTextSymbol.Color = pRgbColor;
                pTextSymbol.Font = pFontDisp;

                // 设置气泡框
                IFormattedTextSymbol pFormattedTextSymbol = pTextSymbol as IFormattedTextSymbol;
                pFormattedTextSymbol.Background = CreateBalloonCallout(pLabelPoint.X, pLabelPoint.Y) as ITextBackground;
                pFormattedTextSymbol.Direction = esriTextDirection.esriTDAngle;

                // 创建文本元素
                ITextElement pTextElement = new TextElement() as ITextElement;
                pTextElement.Symbol = pTextSymbol;
                pTextElement.Text = pFeature.get_Value(fieldIndex).ToString();

                // 元素位置
                IPoint pPoint = new ESRI.ArcGIS.Geometry.Point();
                pPoint.SpatialReference = pLabelPoint.SpatialReference;
                pPoint.X = pLabelPoint.X - 50;
                pPoint.Y = pLabelPoint.Y + 100;

                // 添加文本元素
                IElement pElement = pTextElement as IElement;
                pElement.Geometry = pPoint;
                pGraphicsContainer.AddElement(pElement, 0);
                pFeature = pFeatureCursor.NextFeature();
            }

            // 刷新地图
            System.Runtime.InteropServices.Marshal.ReleaseComObject(pFeatureCursor);
            pActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null);
        }

        // 创建气泡框
        private IBalloonCallout CreateBalloonCallout(double x, double y)
        {
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 225;
            pRgbColor.Blue = 225;
            pRgbColor.Green = 225;

            // 气泡框填充符号
            ISimpleFillSymbol pSimpleFillSymbol = new SimpleFillSymbol();
            pSimpleFillSymbol.Color = pRgbColor;
            pSimpleFillSymbol.Style = esriSimpleFillStyle.esriSFSSolid;

            // 锚点
            IPoint pPoint = new ESRI.ArcGIS.Geometry.Point();
            pPoint.X = x;
            pPoint.Y = y;

            // 气泡框
            IBalloonCallout pBalloonCallout = new BalloonCallout();
            pBalloonCallout.Style = esriBalloonCalloutStyle.esriBCSRoundedRectangle;
            pBalloonCallout.Symbol = pSimpleFillSymbol;
            pBalloonCallout.LeaderTolerance = 5;
            pBalloonCallout.AnchorPoint = pPoint;
            return pBalloonCallout;
        }
    }
}

运行结果如下图所示：
2.5、牵引线标注
牵引线标注的实现代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.DataSourcesFile;
using ESRI.ArcGIS.DataSourcesGDB;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Output;
using ESRI.ArcGIS.SystemUI;
using stdole;

namespace WinApp
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
            axMapControl1.LoadMxFile(@"C:\Users\DSF\Desktop\data\无标题.mxd");
            axMapControl1.Extent = axMapControl1.FullExtent;
        }

        // 标注
        private void btnLabel_Click(object sender, EventArgs e)
        {
            // 创建颜色
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 255;
            pRgbColor.Green = 0;
            pRgbColor.Blue = 0;

            // 创建字体
            IFontDisp pFontDisp = new StdFont() as IFontDisp;
            pFontDisp.Bold = true;
            pFontDisp.Name = "楷体";
            pFontDisp.Size = 20;

            // 删除已有文本元素
            IActiveView pActiveView = axMapControl1.ActiveView;
            IGraphicsContainer pGraphicsContainer = pActiveView.GraphicsContainer;
            pGraphicsContainer.DeleteAllElements();

            // 获取要素游标
            IFeatureLayer pFeatureLayer = axMapControl1.get_Layer(0) as IFeatureLayer;
            IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;
            IFeatureCursor pFeatureCursor = pFeatureClass.Search(null, true);
            IFeature pFeature = pFeatureCursor.NextFeature();

            // 遍历要素游标
            int fieldIndex = pFeatureClass.Fields.FindField("Name");
            while (pFeature != null)
            {
                // 获取重心
                IArea pArea = pFeature.ShapeCopy as IArea;
                IPoint pLabelPoint = pArea.LabelPoint;

                // 创建文本符号
                ITextSymbol pTextSymbol = new TextSymbol();
                pTextSymbol.Angle = 0;
                pTextSymbol.Color = pRgbColor;
                pTextSymbol.Font = pFontDisp;

                // 设置牵引线
                IFormattedTextSymbol pFormattedTextSymbol = pTextSymbol as IFormattedTextSymbol;
                pFormattedTextSymbol.Background = CreateLineCallout(pLabelPoint.X, pLabelPoint.Y) as ITextBackground;
                pFormattedTextSymbol.Direction = esriTextDirection.esriTDAngle;

                // 创建文本元素
                ITextElement pTextElement = new TextElement() as ITextElement;
                pTextElement.Symbol = pTextSymbol;
                pTextElement.Text = pFeature.get_Value(fieldIndex).ToString();

                 // 元素位置
                IPoint pPoint = new ESRI.ArcGIS.Geometry.Point();
                pPoint.SpatialReference = pLabelPoint.SpatialReference;
                pPoint.X = pLabelPoint.X - 50;
                pPoint.Y = pLabelPoint.Y + 200;

                // 添加文本元素
                IElement pElement = pTextElement as IElement;
                pElement.Geometry = pPoint;
                pGraphicsContainer.AddElement(pElement, 0);
                pFeature = pFeatureCursor.NextFeature();
            }

            // 刷新地图
            System.Runtime.InteropServices.Marshal.ReleaseComObject(pFeatureCursor);
            pActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null);
        }

        // 创建牵引线
        private ILineCallout CreateLineCallout(double x, double y)
        {
            IRgbColor pRgbColor = new RgbColor();
            pRgbColor.Red = 0;
            pRgbColor.Blue = 0;
            pRgbColor.Green = 0;

            // 牵引线样式
            ISimpleLineSymbol pLeaderLine = new SimpleLineSymbol();
            pLeaderLine.Color = pRgbColor;
            pLeaderLine.Width = 1;
            
            // 竖线
            ISimpleLineSymbol pAccentBar = new SimpleLineSymbol();
            pAccentBar.Color = pRgbColor;

            // 锚点
            IPoint pPoint = new ESRI.ArcGIS.Geometry.Point();
            pPoint.X = x;
            pPoint.Y = y;

            // 创建牵引线
            ILineCallout pLineCallout = new LineCallout();
            pLineCallout.Style = esriLineCalloutStyle.esriLCSUnderline;
            pLineCallout.Border = null;
            pLineCallout.AccentBar = pAccentBar;
            pLineCallout.LeaderLine = pLeaderLine;
            pLineCallout.AnchorPoint = pPoint;
            return pLineCallout;
        }
    }
}

运行结果如下图所示：

3、结语

其实ArcEngine中的标注功能是很强大的，有兴趣的同志可以继续深入了解。