Obtain the PickFirst Selection Set (.NET)

The PickFirst selection set is created when you select objects prior to starting a command. Several conditions must be present in order to obtain the objects of a PickFirst selection set, these conditions are:

• PICKFIRST system variable must be set to 1
• UsePickSet command flag must be defined with the command that should use the PickFirst selection set
• Call the SelectImplied method to obtain the PickFirst selection set

The SetImpliedSelection method is used to clear the current PickFirst selection set.

Get the Pickfirst selection set

This example displays the number of objects in the PickFirst selection set and then requests the user to select additional objects. Before requesting the user to select objects, the current PickFirst selection set is cleared with the SetImpliedSelection method.

C# Example

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
 
[CommandMethod("CheckForPickfirstSelection", CommandFlags.UsePickSet)]
public static void CheckForPickfirstSelection()
{
    // Get the current document
    Editor acDocEd = Application.DocumentManager.MdiActiveDocument.Editor;

    // Get the PickFirst selection set
    PromptSelectionResult acSSPrompt;
    acSSPrompt = acDocEd.SelectImplied();

    SelectionSet acSSet;

    // If the prompt status is OK, objects were selected before
    // the command was started
    if (acSSPrompt.Status == PromptStatus.OK)
    {
        acSSet = acSSPrompt.Value;

        Application.ShowAlertDialog("Number of objects in Pickfirst selection: " +
                                    acSSet.Count.ToString());
    }
    else
    {
        Application.ShowAlertDialog("Number of objects in Pickfirst selection: 0");
    }

    // Clear the PickFirst selection set
    ObjectId[] idarrayEmpty = new ObjectId[0];
    acDocEd.SetImpliedSelection(idarrayEmpty);

    // Request for objects to be selected in the drawing area
    acSSPrompt = acDocEd.GetSelection();

    // If the prompt status is OK, objects were selected
    if (acSSPrompt.Status == PromptStatus.OK)
    {
        acSSet = acSSPrompt.Value;

        Application.ShowAlertDialog("Number of objects selected: " +
                                    acSSet.Count.ToString());
    }
    else
    {
        Application.ShowAlertDialog("Number of objects selected: 0");
    }
}