在pcu50上运行（本地DDE）。
doconcd上找840d_FBR.PDF.
8.4.1 Establishing a DDE connection with Visual Basic
For the standard Visual Basic controls that are DDE enabled, e.g.

 Label

 Textbox

 Picture
Link Service and Link Topic are combined in the property (attribute) "LinkTopic".
They are separated by the pipe symbol "" (e.g. LinkTopic "ncddelocal").