How can you get the spatial reference of a map dataframe?

[tzz_12]

I was wondering how can I get the spatial reference of the map dataframe? I tried to find the answer searching the online resources with no luck. I appreciate the help. Is it possible to change the spatial reference of the dataframe using C#/ ArcGIS Pro SDK? 

I want to find out the current spatial reference of the dataframe to create a feature class with an appropriate spatial reference for accurate calculation. If the dataframe does not meet the criteria (e.g. not a projected spatial reference), I want to change it to a appropriate spatial reference. 

Thanks for your help!

[RichardDaniels · Accepted solution]

This is actually one of the simpler properties you can get from the map since you do not have to be async or queuedTask.Run.  See Map Class—ArcGIS Pro

var myMap = MapView.Active;
SpatialReference mySpatialReference = mapView.Map.SpatialReference;
if (mySpatialReference.GcsWkid == 3857) //if web Mercator then
  {
  //do some work
   }

[tzz_12]

Thanks Richard! I actually figured it out. 

[Wolf]

In order to change the Spatial Reference for the Map you have to use the SetSpatialReference of the Map class: SetSpatialReference Method (Map)—ArcGIS Pro.  

For this you have to use QueuedTask.Run:

try
{
  // Get the active map view.
  var mapView = MapView.Active;
  if (mapView == null) return;
  // If Spatial Reference is already have Web Mecartor do nothing
  if (mapView.Map.SpatialReference.Equals(SpatialReferences.WebMercator)) return;
  _= QueuedTask.Run(() =>
  {
    // Run within QueuedTask
    mapView.Map.SetSpatialReference(SpatialReferences.WebMercator);
  });
}
catch (Exception ex)
{
  MessageBox.Show (ex.ToString ());
}

[tzz_12]

Thanks Wolf! If the spatial reference isn't Web Mercator, will Line 11 change the spatial reference of the dataframe to Web Mercator? 

[Wolf]

I am not sure what you mean with dataframe, but this is what my code snippet does:

Before running the code snippet, my Map is using the NAD 1983 spatial reference

After i run my code snippet that Spatial Reference changed to Web Mercator