这是一个flash源文件，效果很好，测试平台为flash 8.0（如果提示问题请选择合适的版本试试），代码的效果是：距离函数-This is a flash source file, the effect is very good, the test platform for Flash 8 ( if the question please choose the right version to try), code effect is: distance function

实现了Flex中有向线的功能，可以绘制有向线，自动计算距离使箭头处在线中部位置。-Flex has realized the function of the line, you can draw the line there, automatically calculates the distance the arrow at the central online location.

在线远程教育系统，具有白板功能，采用Flex，可以部署在FMS上(Online distance education system has whiteboard function. It can be deployed on FMS with Flex.)