EditorWindow.OnSelectionChange()

Description

Called whenever the selection has changed.

Saves the current selection and load it later with a simple click.

// Simple example that lets you save the current selection and load it.

using UnityEngine;
using UnityEditor;
using System.Collections;

public class ExampleClass : EditorWindow
{
    private int[] selectionIDs;

    [MenuItem("Example/Selection Saver")]

    private static void Init()
    {
        ExampleClass window = (ExampleClass)GetWindow(typeof(ExampleClass));
        window.Show();
    }

    void OnGUI()
    {
        if (GUILayout.Button("Save"))
            SaveSelection();
        if (GUILayout.Button("Load"))
            LoadLastSavedSelection();
    }

    void OnSelectionChange()
    {
        selectionIDs = Selection.instanceIDs;
    }

    private void SaveSelection()
    {
        var saveStr = "";
        foreach (int i in selectionIDs)
        {
            saveStr += i.ToString() + ";";
        }
        saveStr = saveStr.TrimEnd(char.Parse(";"));
        EditorPrefs.SetString("SelectedIDs", saveStr);
    }

    private void LoadLastSavedSelection()
    {
        string[] strIDs = EditorPrefs.GetString("SelectedIDs").Split(char.Parse(";"));

        int[] ids = new int[strIDs.Length];
        for (var i = 0; i < strIDs.Length; i++)
            ids[i] = int.Parse(strIDs[i]);
        Selection.instanceIDs = ids;
    }
}