protected async override void OnAttached()
{
try
{
base.OnAttached();
// Verify that the behavior is attached to a map with a valid WKID and that a
// query string is present
if (AssociatedObject != null &&
AssociatedObject.SpatialReference != null &&
AssociatedObject.SpatialReference.WKID > 0 &&
HtmlPage.Document != null &&
HtmlPage.Document.QueryString != null)
{
// Put query string values in a case-insensitive dictionary
var queryString = new Dictionary <string, string>(HtmlPage.Document.QueryString, StringComparer.InvariantCultureIgnoreCase);
// Check whether query string contains center
if (queryString.ContainsKey("center"))
{
// get the center string
string centerString = queryString["center"];
// get the list delimiter for the current culture (making sure to account for cultures that use delimiters other than comma)
char listDelimiter = CultureInfo.CurrentCulture.TextInfo.ListSeparator[0];
// Split extent string into discrete values
string[] centerPointVals = centerString.Split(listDelimiter);
double x, y;
// Verify that the expected number of values are present, that they are numeric, and convert the values to doubles
IFormatProvider numericFormat = CultureInfo.CurrentCulture.NumberFormat;
if ((centerPointVals.Length == 2 || centerPointVals.Length == 3) &&
double.TryParse(centerPointVals[0], NumberStyles.Number, numericFormat, out x) &&
double.TryParse(centerPointVals[1], NumberStyles.Number, numericFormat, out y))
{
// get WKID from the map attached to the behavior
int currentWkid = AssociatedObject.Extent.SpatialReference.WKID;
int queryStringWkid = currentWkid;
// Check whether a WKID was specified (will be the 3rd parameter if present) and grab it if so
if (centerPointVals.Length == 3 && !int.TryParse(centerPointVals[2], out queryStringWkid))
{
// invalid WKID specified, fire InitializationFailed and exit
OnInitializationFailed(new Exception(Strings.InvalidWkid));
return;
}
// Initialize a point with the same spatial reference as the attached map
MapPoint queryStringPoint = new MapPoint(x, y)
{
SpatialReference = new SpatialReference(queryStringWkid)
};
// check whether the specified WKID is different than that of the attached map, meaning the point needs to be projected
if (queryStringWkid != currentWkid)
{
WebMercator wm = new WebMercator();
// Use convenience methods to convert between WGS 84 and Web Mercator if possible
if (isWebMercator(queryStringWkid) && isWgs84(currentWkid))
{
queryStringPoint = (MapPoint)wm.ToGeographic(queryStringPoint);
}
else if (isWgs84(queryStringWkid) && isWgs84(currentWkid))
{
queryStringPoint = (MapPoint)wm.FromGeographic(queryStringPoint);
}
else if (!string.IsNullOrEmpty(MapApplication.Current.Urls.GeometryServiceUrl))
{
// Conversion is not between WGS 84 and Web Mercator, so a call to a geometry service is necessary to perform
// the projection
try
{
GeometryService gs = new GeometryService(MapApplication.Current.Urls.GeometryServiceUrl);
var g = new Graphic()
{
Geometry = queryStringPoint
};
var sr = new SpatialReference(currentWkid);
var result = await gs.ProjectTaskAsync(new Graphic[] { g }, sr);
queryStringPoint = (MapPoint)result.Results[0].Geometry;
}
catch (Exception ex)
{
// Projection failed. Fire InitializationFailed event and return.
OnInitializationFailed(ex);
return;
}
}
}
var panDuration = AssociatedObject.PanDuration;
AssociatedObject.PanDuration = TimeSpan.FromSeconds(0);
AssociatedObject.PanTo(queryStringPoint);
AssociatedObject.PanDuration = panDuration;
}
}
}
// Fire Initialized event
OnInitialized();
}
catch (Exception ex)
{
// Raise InitializationFailed event
OnInitializationFailed(ex);
}
}