The
NetDDE is an extension of the
DDE communication standard for the network communication. In the
Windows OS 2000 and higher it is the
Service and it is advisable to set the service as "run automatically".
Caution. From certain reasons it is necessary to have installed the network
Netbios protocol or
NetBEUI for the
NetDDE functionality. It is possible to install the stand-alone
NetBEUI protocol in
Windows OS or to have
Netbios services switched on in the
TCP/IP protocol. But these protocols are not routeable - it means that
by the NetDDE communication it is possible to transfer data only in one local network. In large company networks that consist from more servers it is impossible to communicate by the
NetDDE! This is also the reason why it is better to use prefarably other types of communications, for example
XML data sharing.
Setting NetDDE server side:
If we want to provide the
"PROMOTIC" service,
"OBJECT" topic,
"item1" item and all this from the computer named "
USER", then it is necessary to execute the following steps:
- Start the NetDDE (for the description see above).
- Start the DDEshare.exe program, which is the DDE manager. By this, the selection of the DDE data offer is made on the computer where the DDEshare.exe was started.
In the
Share menu in the
DDE Shares item a new share is added after pressing the
Add and
Share buttons. It is necessary to enter:
- Share name: the name terminated by the '$' char, for example MYSHARE$
- Application name: for example PROMOTIC
- Topic name: for example OBJECT
- Acces type: FULL (for read and write) or READONLY
- Grant acces to all items
Confirm the window by the "
OK" button. Press the "
Trust share" button and a window appears where options are checked for the share
- Start Application Enable
- Initiate to Application Enable
Confirm all by the "
OK" button and close the program. The
Windows OS stores these data into its database that is preserved even after the restart of the computer.
Setting NetDDE client side:
Start the
NetDDE (for the description see above). The remote client refers to the service by:
- service: '\\USER\NDDE$'
- topic: 'MYSHARE$'
- item: item name of the "PROMOTIC" service, of the "OBJECT" topic that the computer with the network name "USER" offers by the above mentioned way by the NetDDE, in this case for example "item1".
Example:
Example in the Excel format
'\\UZIVATEL\NDDE$'|'MYSHARE$'!item1