/// <summary>
        /// Intercepts Command.Execute() and launches a <c>KeyManager</c> prompting the user to manage a key.
        /// </summary>
        protected override void ExecuteCore(ConfigurationNode node)
        {
            ExpressionEditorFormUI formUI = new ExpressionEditorFormUI();

            formUI.RuleName = SR.AuthorizationRuleNodeName;
            DialogResult result = formUI.ShowDialog();

            if (result == DialogResult.OK)
            {
                base.ExecuteCore(node);
                AuthorizationRuleNode ruleNode = (AuthorizationRuleNode)ChildNode;
                ruleNode.Expression = formUI.Expression;
            }
        }
 public ExpressionEditor()
 {
     formUI = new ExpressionEditorFormUI();
 }