c# 进行AE开发时，如何在地图上定位出一个点

一、文本形式的气泡提示框

由于本人是初学，所以具体的含义尚未弄清楚，直接给出代码吧！

        /// <summary>
        /// ARCGIS Label标记
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void tsmi_MapOperate_LocationMark_Click(object sender, EventArgs e)
        {
            ITextElement te = createTextElement(120.85811111, 30.21402778, "潮位站--上虞");
            this.axMapControl1.ActiveView.GraphicsContainer.AddElement(te as IElement, 1);
            this.axMapControl1.Refresh(esriViewDrawPhase.esriViewGraphics, null, null);
        }


        public ITextElement createTextElement(double x_longitude, double y_latitude, string text_content)
        {

            IBalloonCallout bc = CreateBalloonCallout(x_longitude, y_latitude);
            IRgbColor color_rgb = new RgbColorClass();
            ITextSymbol text_symbol = new TextSymbolClass();
            IFormattedTextSymbol ftext_symbol;
            IPoint point = new PointClass();
            ITextElement text_elt = new TextElementClass();
            double width, height;
            IElement e;

            color_rgb.Green = 255;
            text_symbol.Color = color_rgb;

            ftext_symbol = text_symbol as IFormattedTextSymbol;
            ftext_symbol.Background = bc as ITextBackground;

            //fts.Size = 8;
            text_symbol.Size = 8;

            width = this.axMapControl1.Extent.Width / 13;
            height = this.axMapControl1.Extent.Height / 20;
            point.PutCoords(x_longitude + width, y_latitude + height);
            
            //IMarkerElement me = new MarkerElementClass();
            text_elt.Symbol = text_symbol;
            text_elt.Text = text_content;

            e = text_elt as IElement;
            e.Geometry = point;


            return text_elt;

        }

        public IBalloonCallout CreateBalloonCallout(double x, double y)
        {
            IRgbColor color_rgb = new RgbColorClass();
            ISimpleFillSymbol simpleFillSbl = new SimpleFillSymbolClass();
            IPoint point = new PointClass(); ;
            IBalloonCallout balloonCallout = new BalloonCalloutClass(); // 气球类型的插图编号

            color_rgb.Red = 255;
            color_rgb.Green = 255;
            color_rgb.Blue = 200;

            simpleFillSbl.Color = color_rgb;
            simpleFillSbl.Style = esriSimpleFillStyle.esriSFSSolid;
            point.PutCoords(x, y);

            balloonCallout.Style = esriBalloonCalloutStyle.esriBCSRoundedRectangle;
            balloonCallout.Symbol = simpleFillSbl;
            balloonCallout.LeaderTolerance = 10;
            balloonCallout.AnchorPoint = point;

            return balloonCallout;
        }