private void btnAdd_Click(object sender, EventArgs e)
        {
            frmNewNetworkAttribute attribute = new frmNewNetworkAttribute();

            if (attribute.ShowDialog() == DialogResult.OK)
            {
                string[] items = new string[]
                {
                    "", "", attribute.NetworkAttribute.Name,
                    CommonHelper.GetUsageTypeDescriptor(attribute.NetworkAttribute.UsageType),
                    CommonHelper.GetNetworkUnitTypeDescriptor(attribute.NetworkAttribute.Units),
                    CommonHelper.GetDataTypeDescriptor(attribute.NetworkAttribute.DataType)
                };
                INetworkConstantEvaluator  evaluator        = new NetworkConstantEvaluatorClass();
                IEvaluatedNetworkAttribute networkAttribute = attribute.NetworkAttribute as IEvaluatedNetworkAttribute;
                evaluator.ConstantValue = 0;
                networkAttribute.set_DefaultEvaluator(esriNetworkElementType.esriNETEdge, evaluator as INetworkEvaluator);
                networkAttribute.set_DefaultEvaluator(esriNetworkElementType.esriNETJunction,
                                                      evaluator as INetworkEvaluator);
                networkAttribute.set_DefaultEvaluator(esriNetworkElementType.esriNETTurn, evaluator as INetworkEvaluator);
                ListViewItem item = new ListViewItem(items)
                {
                    Tag = attribute.NetworkAttribute
                };
                this.listView1.Items.Add(item);
                NewNetworkDatasetHelper.NewNetworkDataset.Attributes.Add(attribute.NetworkAttribute);
            }
        }
        public static void SetDefaultEvaluator(IEvaluatedNetworkAttribute netAttribute, object defaultValue, esriNetworkElementType eType)
        {
            INetworkConstantEvaluator constEvaluator = new NetworkConstantEvaluatorClass();

            constEvaluator.ConstantValue = defaultValue;
            INetworkEvaluator eval = constEvaluator as INetworkEvaluator;

            netAttribute.set_DefaultEvaluator(eType, eval);
        }
		public static void SetDefaultEvaluator(IEvaluatedNetworkAttribute netAttribute, object defaultValue, esriNetworkElementType eType)
		{
			INetworkConstantEvaluator constEvaluator = new NetworkConstantEvaluatorClass();
			constEvaluator.ConstantValue = defaultValue;
			INetworkEvaluator eval = constEvaluator as INetworkEvaluator;
			netAttribute.set_DefaultEvaluator(eType, eval);
		}