If you have an SSDT project in visual studio and want to get the version of sql it is targetting because everything is internal :( do this!

targetSqlVersion.cs

string GetTargetSqlServerVersion(){

var dte = (DTE)GetService(typeof(DTE));
var project = dte.ActiveDocument.ProjectItem.ContainingProject;

  return project.GetType().GetProperty("Globals").GetValue(project).GetType().GetProperty("Parent").GetValue(project.GetType().GetProperty("Globals").GetValue(project)).GetType().GetProperty("DatabaseSchemaProvider").GetValue(project.GetType().GetProperty("Globals").GetValue(project).GetType().GetProperty("Parent").GetValue(project.GetType().GetProperty("Globals").GetValue(project))).GetType().GetProperty("Platform").GetValue(project.GetType().GetProperty("Globals").GetValue(project).GetType().GetProperty("Parent").GetValue(project.GetType().GetProperty("Globals").GetValue(project)).GetType().GetProperty("DatabaseSchemaProvider").GetValue(project.GetType().GetProperty("Globals").GetValue(project).GetType().GetProperty("Parent").GetValue(project.GetType().GetProperty("Globals").GetValue(project))))

}