将屏幕转换为SP 4326

Question

我正在使用Esri for .NET。我使用ScreenToLocation函数通过鼠标单击来捕获屏幕坐标。我如何将这个映射转换为4326的SP？

MapPoint mapPoint = Mapview.ScreenToLocation(screenPoint); 

我的地图不是我点击地图的地方。我得到的坐标为5423799.44921864，-267641.097678069

Answer 1

您是使用ArcGIS Runtime for windows store还是wpf的运行时？

无论如何，你正在获得一个WebMercator点。为了空间参考之间进行转换需要使用上wpf在winstore

的GeometryService的工程方法或GeometryEngine或者，如果你喜欢做转换WebMercator（三千八百五十七分之一十万二千百）到WGS84 （4326）同步的代码，你可以做：

private const double R_MAJOR = 6378137.0; 
private const double R_MINOR = 6356752.3142; 

public MapPoint PointToWGS84(double x, double y) 
{   
    double originShift = 2 * Math.PI * R_MAJOR/2.0; 
    double mx = (x/originShift) * 180.0; 
    double my = (y/originShift) * 180.0; 
    my = (180/Math.PI) * (2 * Math.Atan(Math.Exp(my * Math.PI/180.0)) - Math.PI/2.0); 
    return new MapPoint(mx, my, new SpatialReference(WGS84)); 
} 

从WGS84到WM

public MapPoint PointToWM(double x, double y) 
{ 
    double originShift = 2 * Math.PI * R_MAJOR/2.0; 
    double mx = x * originShift/180.0; 
    double my = Math.Log(Math.Tan((90.0 + y) * Math.PI/360.0))/(Math.PI/180.0); 
    my = my * originShift/180.0; 
    return new MapPoint(mx, my, new SpatialReference(102100)); 
} 

请注意，此代码仅适用于WM来往/来自WGS。对于其他转换，您必须始终使用GeometryService