js动态实现图片缩放比例，区别于普通的图片控件往往使用图片失真。-js dynamic realization of image scaling, different from the normal picture control is often used to image distortion.

ESRI 的ArcGIS+API+for+JS+开发教程 资料(ESRI's ArcGIS+API+for+JS+ development tutorial data)