基于地图开发控件GMap.Net 使用 (五) 原创用户自定义标签图片

时间：2011-06-02 来源：Eric·liu

最近看到 fangping朋友的提问问是否可以自定义标签，相信大家对此问题都挺关注。回头看看Gmap动态库还真没提供此功能。自己添加一个！打开开源源码创建一个类名为GMapMarkerImage的类。此类功能：用户可添加自定义图片标签。

添加源码如下：

View Code

  public class GMapMarkerImage : GMapMarker
    {
        public float? Bearing;

        private Image userImage=null;

        public GMapMarkerImage(PointLatLng p)
            : base(p)
        {
            Size = new System.Drawing.Size(Resources.bigMarkerGreen.Width, Resources.bigMarkerGreen.Height);
            Offset = new Point(-10, -34);
        }

        public GMapMarkerImage(PointLatLng p ,string imageFile)
            : base(p)
        {
            Size = new System.Drawing.Size(Resources.bigMarkerGreen.Width, Resources.bigMarkerGreen.Height);
            Offset = new Point(-10, -34);
            try
            {
                userImage = Bitmap.FromFile(imageFile);
                userImage = new Bitmap(0, 0);
            }
            catch
            {
 
            }
        }

        public GMapMarkerImage(PointLatLng p, Image imageFile)
            : base(p)
        {
            Size = new System.Drawing.Size(Resources.bigMarkerGreen.Width, Resources.bigMarkerGreen.Height);
            Offset = new Point(-10, -34);
            userImage = imageFile;
        }

       static readonly Point[] Arrow = new Point[] { new Point(-7, 7), new Point(0, -22), new Point(7, 7), new Point(0, 2) };

       public override void OnRender(Graphics g)
       {
#if !PocketPC
           
           g.TranslateTransform(ToolTipPosition.X, ToolTipPosition.Y);

           g.ResetTransform();

           if (!Bearing.HasValue)
           {
               g.DrawImageUnscaled(userImage, LocalPosition.X, LocalPosition.Y);
           }
#else
            DrawImageUnscaled(g, Resources.shadow50, LocalPosition.X, LocalPosition.Y);
            DrawImageUnscaled(g, Resources.marker, LocalPosition.X, LocalPosition.Y);
#endif
           base.OnRender(g);
       }