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

/// <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;
}