MapXtreme 应用[地图的放大、缩小和还原]

        private void toolStripButton1_Click(object sender, EventArgs e)
        {
            MapInfo.Geometry.Distance previousZoom = this.MapControl_DEMO.Map.Zoom;
            MapControl_DEMO.Map.Zoom = new MapInfo.Geometry.Distance(previousZoom.Value / 2, previousZoom.Unit);
        }

        private void toolStripButton2_Click(object sender, EventArgs e)
        {
            MapInfo.Geometry.Distance previousZoom = this.MapControl_DEMO.Map.Zoom;
            MapControl_DEMO.Map.Zoom = new MapInfo.Geometry.Distance(previousZoom.Value * 2, previousZoom.Unit);
        }

        private void toolStripButton3_Click(object sender, EventArgs e)
        {
            MapControl_DEMO.Map.Center = new MapInfo.Geometry.DPoint(92.8118000049144, 30044.4600000065);//92.8118000049144,Y=30044.4600000065
            MapControl_DEMO.Map.Zoom = new MapInfo.Geometry.Distance(28000, MapInfo.Geometry.DistanceUnit.Mile);
        }

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MapInfo.Geometry.DistanceUnit

namespace MapInfo.Geometry
{
    public enum DistanceUnit
    {
        Mile = 0,
        Kilometer = 1,
        Inch = 2,
        Foot = 3,
        Yard = 4,
        Millimeter = 5,
        Centimeter = 6,
        Meter = 7,
        SurveyFoot = 8,
        NauticalMile = 9,
        Degree = 13,
        Link = 30,
        Chain = 31,
        Rod = 32,
    }
}

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