Flex - 客户端导出图片

package
{
	import flash.display.BitmapData;
	import flash.display.DisplayObject;
	import flash.display.DisplayObjectContainer;
	import flash.geom.Matrix;
	import flash.geom.Point;
	import flash.net.FileReference;
	import flash.utils.ByteArray;
	
	import mx.controls.Alert;
	import mx.graphics.codec.PNGEncoder;

	public class PictureExporter
	{
		public function PictureExporter()
		{
		}
		
		/**
		 * 导出图片
		 */
		public static function exportChart(d:DisplayObject, fileName:String = 'chart.png'):void{  
			var dt:DisplayObject = d;  
			var bd:BitmapData = getBitMapData(dt,dt.parent);     
			var fr:Object = new FileReference();  
			if(fr.hasOwnProperty("save")){  
				var encoder:PNGEncoder = new PNGEncoder();  
				var data:ByteArray = encoder.encode(bd);  
				fr.save(data,fileName);  
			}else{  
				Alert.show("当前的flash player版本不支持此功能,请安装10.0.0以上版本！","提示");  
			}  
		}   
		//获得对象的BitMapData  
		private static function getBitMapData(mc:DisplayObject,container:DisplayObjectContainer):BitmapData{  
			var bmpData:BitmapData = new BitmapData(mc.width,mc.height,true,0xffffff);  
			var bounds:Object = mc.getBounds(mc);  
			var bounds2:Object = container.getBounds(container);  
			var matrix:Matrix = mc.transform.matrix.clone();  
			var point0:Point = container.globalToLocal(mc.localToGlobal(new Point(bounds.x,bounds.y)));  
			var point1:Point = container.globalToLocal(mc.localToGlobal(new Point(bounds.x,bounds.y+bounds.height)));  
			var point2:Point = container.globalToLocal(mc.localToGlobal(new Point(bounds.x+bounds.width,bounds.y)));  
			var point3:Point = container.globalToLocal(mc.localToGlobal(new Point(bounds.x+bounds.width,bounds.y+bounds.height)));  
			var point:Point = point0;  
			
			(point.x>point1.x)&&(point.x=point1.x);  
			(point.x>point2.x)&&(point.x=point2.x);  
			(point.x>point3.x)&&(point.x=point3.x);  
			(point.y>point1.y)&&(point.y=point1.y);  
			(point.y>point2.y)&&(point.y=point2.y);  
			(point.y>point3.y)&&(point.y=point3.y);  
			matrix.tx = mc.x - point.x;  
			matrix.ty = mc.y - point.y;  
			bmpData.draw(mc,matrix);  
			return bmpData;  
		}
	}
}