raction(drawTool);
            } 
            //实例化交互绘制类对象并添加到地图容器中
            drawTool = new ol.interaction.Draw({
                type: 'Circle',
                //绘制层数据源
                source: interActionSource
            });
            map.addInteraction(drawTool);
            //点击查询的回调函数
            drawTool.on('drawend', drawToolCallback_Circle);
        }
        
        function drawToolCallback_Circle(feature)
        {
      