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How to get points longitude and latitude by it's id?

#1

Hello all ,
i have a simple problem i have plotted a lot of points by mouse click and gave its point an id , i need to get any of these point longitude or latitude by calling its ID , how can i do that ?

thanks in advance

#2

Hi Mostafa20015,

I think this sample should be helpful.

Any question please let us know.

Regards,

Ethan

#3

thanks ethan ,
but unfortunately it is not what i want , now i have to plot a circle its center is point_x , this point_x is a dummy point i have created on map_click event , to achieve my purpose i have to get this dummy point_x longitude and latitude by calling it’s id

EllipseShape ellipseShape = new EllipseShape(point_x , CircleRadius, GeographyUnit.DecimalDegree, DistanceUnit.Kilometer);

#4

Hi Mostafa,

It looks you want to find the feature by its id, that’s even more simple.

We have the API named layer.QueryTools.GetFeatureById, it can works for it.

If I still misunderstand you please describe your requirement more detail.

Regards,

Ethan

#5

hello ethan , im sorry for disturbance

here is a part of code which plot a point on mouse click event

private void winformsMap1_MouseClick(object sender, MouseEventArgs e)
        {         
            if (e.Button == MouseButtons.Right)
            {              
                InMemoryFeatureLayer shapeLayer = (InMemoryFeatureLayer)
                winformsMap1.FindFeatureLayer("Shape");
                System.Drawing.Point screenPointEnd = e.Location;              
                RectangleShape extent = winformsMap1.CurrentExtent;               
                ScreenPointF currentPoint = new ScreenPointF(screenPointEnd.X, screenPointEnd.Y);              
                PointShape endPoint = ExtentHelper.ToWorldCoordinate(extent, currentPoint,winformsMap1.Width, winformsMap1.Height);                
                shapeLayer.InternalFeatures.Add("shape" + y, new Feature(endPoint));           
                winformsMap1.Refresh(winformsMap1.Overlays["PointOverlay"]);
                y++;
            }
        }

after plotting five points for example [first point id is “shape1” , and 2nd point id is “shape2” …till “shape5”]
, i need to draw a circle it’s center is one of these point according its id (for example i will type a point id in textbox = “shape5”)
now i need this shape5 point is the center of a circle i want to plot

this part of code for plotting a circle

   int q = 1;  //circle id counter
    private void button7_Click(object sender, EventArgs e)
    {          
        InMemoryFeatureLayer shapeLayer = (InMemoryFeatureLayer)winformsMap1.FindFeatureLayer("Shape");
        InMemoryFeatureLayer CircleLayer = (InMemoryFeatureLayer)winformsMap1.FindFeatureLayer("CircleLayer");          
        // circle center point 
        PointShape circle_center= new PointShape(30,30);
        //get circle radius from Circle radius textbox
        double CircleRadius = Convert.ToDouble(textBox2.Text);          
        EllipseShape ellipseShape = new EllipseShape(circle_center,CircleRadius, GeographyUnit.DecimalDegree, 		DistanceUnit.Kilometer);
        CircleLayer.InternalFeatures.Add("circle" + q  ,new Feature(ellipseShape));
        CircleLayer.InternalFeatures.Add("circle_center" + q ,new Feature(GPSpointShape));      	
        q++;//increasind circle id counter each time we plot a circle
        winformsMap1.Refresh(winformsMap1.Overlays["PointOverlay"]);
    }

BestRegards

#6

hello all ,
that was i wanted

//get a longtude and latitue of point by its ID and use it as a center point for circle
                PointShape circle_center = (PointShape)shapeLayer.InternalFeatures["shape" + PID].GetShape();
#7

Hi Mostafa,

Yes this way can works for your scenario.

Thanks for your update.

Regards,

Ethan