MapObjects2自定义符号实现

公司一个项目正在用MapObjects来实现基于桌面的地图操作，在地址定位时，MapObjects中提供了一些符号来表示poi，但是总是感觉不能直观的表达意思，所以就打算用图片的形式来显示一个poi，找了很多资料，终于琢磨出来，贴上来与大家共享

自定义标记 CustomMarker 代码如下

using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing;

namespace EstateMgtUI.Application
{
    public class CustomMarker : ESRI.MapObjects2.Custom.ICustomMarker
    {
        #region
        private IntPtr m_hdc;
        private System.Drawing.Graphics m_graphics;
        private Image image;

        public CustomMarker(string fileName)
        {
            image = Image.FromFile(fileName);
            //Bitmap image = new Bitmap(fileName);
            m_graphics = Graphics.FromImage(image);
        }
        #endregion


        #region ICustomMarker 成员
        //绘制图片
        void ESRI.MapObjects2.Custom.ICustomMarker.Draw(int hDC, int x, int y)
        {
            //calls drawing primitve to draw the symbol        
            int height = this.image.Height;
            int width = this.image.Width;
            //this.m_CustomStyle继承自CustomSym
            //绘制图形
            m_graphics.DrawImage(this.image, x - width / 2, y - height / 2);
        }
        //刷新m_graphics
        void ESRI.MapObjects2.Custom.ICustomMarker.ResetDC(int hDC)
        {
            //Cleans up and re-establishes the original device context
            if (m_graphics != null)
            {
                m_graphics.ReleaseHdc(m_hdc);
                m_graphics.Dispose();
                m_graphics = null;
            }
        }
        //设置m_graphics
        void ESRI.MapObjects2.Custom.ICustomMarker.SetupDC(int hDC, double dpi, object pBaseSym)
        {
            //establishes the device context and sets up symbol characteristics
            m_hdc = new IntPtr(hDC);

            //Get the graphics drawing surface
            m_graphics = System.Drawing.Graphics.FromHdc(m_hdc);
        }

        #endregion
    }
}

使用自定义符号如下

layer = new MapObjects2.MapLayer();
layer.GeoDataset = _environment.m_db.FindGeoDataset("temp");
CustomMarker mark = new CustomMarker("D://qq.bmp");
layer.Symbol.Custom = mark;

效果如下

好，基本内容已经完了。至于需要引用什么dll，看代码应该就明白了。

欢迎交流