扩展easy ui tree 层级（level）

$.extend($.fn.tree.methods, {
				getLevel:function(jq,target){
					var l = $(target).parentsUntil("ul.tree","ul");
					return l.length+1;
				}
			});


$('#basicLineTypeTree').tree({
				url: 'getBasicLineTypes.action',
				onClick:function(node){
					basicLineTypeId = node.id;
					refreshPage('#baseLineAttrTab');
					$('#baseLineAttrTab').datagrid('reload',{'basicLineTypeId':node.id});
					//清空table选择项
					$('#baseLineAttrTab').datagrid('unselectAll');
				},
				onContextMenu: function(e, node){
					e.preventDefault();
					$('#basicLineTypeTree').tree('select', node.target);
					var level =  $('#basicLineTypeTree').tree("getLevel",node.target);
					$('#basicLineTypeTreeMenu').menu('show', {
						left: e.pageX,
						top: e.pageY
					});
				}
			});