在Windows中，冒号不是文件名中允许的字符.或者，更准确地说，它用于寻址文件的备用数据流.因此，asdf:qwer寻址名为asdf的文件的名为qwer的流.

Colon is not an allowed character in a filename in Windows. Or, more precisely, it is used to address an Alternate Data Stream of a file. So, asdf:qwer addresses the stream named qwer of the file named asdf.

这与反斜杠非常相似. asdf\qwer也不是有效的文件名，而是指向文件夹asdf的文件qwer.

This is very similar to the backslash. asdf\qwer is also not a valid filename, instead it addresses the file qwer of the folder asdf.