shp文件在ArcMap打开后经常因为原有坐标系无法识别而丢失信息,出现以下提示信息:
"Unknown Spatial Reference
The following data sources you added are missing spatial reference information. This data can be drawn in ArcMap, but cannot be projected."
The following data sources you added are missing spatial reference information. This data can be drawn in ArcMap, but cannot be projected."
原因:因为软件无法识别空间参考信息,所以要先定义椭球体(定义地理坐标系,相当于去掉原有的投影),然后再投影(Projection)。之前我们总想一步到位,软件本来就不识别文件的投影信息,你让它转换到另一个投影下,自然有点难为它了。关于地理坐标系和投影坐标系的区别就不再赘述了。
详情请看原文:http://smiliing.spaces.live.com/blog/cns!FB62DAD013AC3B4E!653.entry