arcgis地图————————icon元素的添加

var myLine ={
							geometry:{
									"x":120.1645790997531,"y":30.30271946186709, 
									"spatialReference":{"wkid":4326}
									}, 
							symbol:{
									"url":"D:/项目/GIS资料/image/crossing-alarm.png", 
									"height":30, 
									"width":18.75, 
									"type":"esriPMS" }
								}; 
				this.graphic = new esri.Graphic(myLine);
				this.businessGraphicsLayer.add(this.graphic);