EditorPrefs.HasKey

Description

Returns true if key exists in the preferences.

Quick notes that last between Unity Sessions.

    // Simple Editor Script that lets you create / save quick notes
    // Between Unity Sessions.

    class QuickNotes extends EditorWindow {

        var note : String = "Notes:\n->\n->";

        @MenuItem("Examples/QuickNotes")
        static function Init() {
            var window  = GetWindow(QuickNotes);
            window.Show();
        }
        function OnGUI() {
            note = EditorGUILayout.TextArea(note,
                GUILayout.Width(position.width-5),
                GUILayout.Height(position.height - 30));
            EditorGUILayout.BeginHorizontal();
            if(GUILayout.Button("Reset"))
                note = "";
            if(GUILayout.Button("Clear Story",GUILayout.Width(72))) {
                note = "Notes:\n->\n->";
            }
            EditorGUILayout.EndHorizontal();
        }
        function OnFocus() {
            if(EditorPrefs.HasKey("QuickNotes"))
                note = EditorPrefs.GetString("QuickNotes");
        }
        function OnLostFocus() {
            EditorPrefs.SetString("QuickNotes",note);
        }
        function OnDestroy() {
            EditorPrefs.SetString("QuickNotes",note);
        }
    }