JSFL 导出图片

jpg:
var imageFileURL = imgsFileUrl + flaNum+"_1.jpg";
select_lockedAndHideLayers(nowPartFlaDoc, false);
nowPartFlaDoc.selectAll();
fl.getDocumentDOM().convertSelectionToBitmap();

var bitMap=fl.getDocumentDOM().selection[0];
var sqIndex = fl.getDocumentDOM().library.findItemIndex(bitMap.libraryItem.name);

var libItem = fl.getDocumentDOM().library.items[sqIndex];
libItem.exportToFile(imageFileURL, 100);

　　

png:
var fileURI = placeFile+nowPartName.split(".fla")[0] + ".png";
nowPartFlaDoc.exportPNG(fileURI, false, true);